Resolve issue: https://github.com/kanaka/noVNC/pull/101

Based on proposal from @mightpenguin:
Matthew Balman <emperor@mightypenguin.org>

If view_only option is set then do not send mouse and keyboard events.
This is not a secure/enforced way to make a client view only. To
enforce view only at the server, most VNC servers support setting
a view only password.

- Remove the images using the old font.

- Simplify the naming of the new control bar icon images.

- Change keyboard input type to 'email'. 'url' type doesn't have
  a space bar.

- Some clarifications to main LICENSE.txt file.

- CSS highlighting of buttons when selected.
- Keyboard button tweaked to allow show/hide toggle of keyboard.
Signed-off-by: Chris Gordon <snorkeyg@gmail.com>

Instead of using Google Font API, use local copy of Orbitron for speed
and also in case Internet connection is flaky or unavailable.

More info about Orbitron font here:
http://www.google.com/webfonts/specimen/Orbitron

Orbitron font is:
Copyright (c) 2009, Matt McInerney <matt@pixelspread.com>

Licensed under SIL Open Font License 1.1
see docs/LICENSE.OFL-1.1 or http://scripts.sil.org/OFL

- Make sure that on iOS the clipping setting is always forced to be
  enabled.
- Hide the showKeyboard button unless connected.
- Use the URL text entry method and disable autocorrect and
  autocapitalize in the show keyboard input box.

Cleanup:

- remove unused changeViewportMeta function from include/ui.js
- remove some debug output and debug CSS.
- rename panel toggle functions and put them in same location in the
  code.
- refactor some code from updateState to updateVisualState routine
  (renamed from updateSettingsState).

API changes (forward compatible):

- Display: add 'viewport' conf option to turn on and off viewport
  mode.
- RFB: add 'viewportDrag' option to enable/disable viewport dragging
  mode.

Other:

- Add clip mode setting to default UI. For touch devices, clipping is
  forced on.
- Use CSS media queries to adjust visual elements based on screen
  size. Especially disconnected logo size/position and button text size.
- Catch page unload while connected and give a confirm dialog.
- Change mouse button selector to a single button that changes between
  ' ', 'L', 'M', 'R' when clicked (empty means mouse is just being
  moved and doesn't send clicks).
- include/ui.js:setViewClip() routine sets the clipping of the
  viewport to the current size of the viewport area (if clipping is
  enabled).
- include/ui.js:setViewDrag() toggles/enables/disables viewport
  dragging mode.
- Add several images for the UI and for Apple devices:
    - images/clipboard.png: clipboard menu icon
    - images/connect.png: connect menu icon
    - images/disconnect.png: disconnect button icon
    - images/keyboard.png: show keyboard button
    - images/move.png: viewport drag/move toggle button
    - images/settings.png: settings menu icon
    - images/screen_320x460.png: iOS app/desktop link start image
    - images/screen_57x57.png: iOS app icon
    - images/screen_700x700.png: full size noVNC image

Another firefox issue is that height: 100% is calculated as 100% of
the containing element even when the containing element is the window.
This means that the size of any sibling element shifts the window size
down by that much and causes the vertical scroll bars to appear. This
doesn't happen in Chrome.

- So instead, put a pad element inside the noVNC_screen element that
  is the size of the control bar. This is hidden by the control bar,
  however, it causes things to be sized correctly.

- Also, rename noVNC_defaultScreen to noVNC_logo.

- Clean some style specification out of the HTML.

- 4 space indenting for HTML and Javascript.
- 2 space indenting for CSS
- Use hanging start curly for conditional blocks

changeViewportMeta() now does viewport changes.

Tested with Safari on iPad for iOS and Asus Transformer for Android.

And DefaultControls to UI.

- Add meta tag to vnc.html and vnc_auto.html so that if Chrome Frame
  is installed, it is used.

- Add detection to default_controls.js that shows a message with
  a Chrome Frame install link if the user is using a version of IE
  without Canvas support.

- Fix web.py so that requests have their connection closed after they
  are completed.  This has been a bug for a while but it prevents
  Chrome Frame from working because Chrome Frame doesn't activate
  until the initial request connection closes.

New API:

To use the RFB object, you now must instantiate it (this allows more
than one instance of it on the same page).

    rfb = new RFB(settings);

The 'settings' variable is a namespace that contains initial default
settings. These can also be set and read using 'rfb.set_FOO()' and
'rfb.get_FOO()' where FOO is the setting name. The current settings
are (and defaults) are:
    - target: the DOM Canvas element to use ('VNC_canvas').
    - encrypt: whether to encrypt the connection (false)
    - true_color: true_color or palette (true)
    - b64encode: base64 encode the WebSockets data (true)
    - local_cursor: use local cursor rendering (true if supported)
    - connectTimeout: milliseconds to wait for connect (2000)
    - updateState: callback when RFB state changes (none)
    - clipboardReceive: callback when clipboard data received (none)

The parameters to the updateState callback have also changed. The
function spec is now updateState(rfb, state, oldstate, msg):
    - rfb: the RFB object that this state change is for.
    - state: the new state
    - oldstate: the previous state
    - msg: a message associate with the state (not always set).

The clipboardReceive spec is clipboardReceive(rfb, text):
    - rfb: the RFB object that this text is from.
    - text: the clipboard text received.

Changes:

- The RFB and Canvas namespaces are now more proper objects. Private
  implementation is no longer exposed and the public API has been made
  explicit. Also, instantiation allows more than one VNC connection
  on the same page (to complete this, DefaultControls will also need
  this same refactoring).

- Added 'none' logging level.

- Removed automatic stylesheet selection workaround in util.js and
  move it to defaultcontrols so that it doesn't interfere with
  intergration.

- Also, some major JSLinting.

- Fix input, canvas, and cursor tests to work with new model.

The following API changes may affect integrators:

    - Settings have been moved out of the RFB.connect() call. Each
      setting now has it's own setter function: setEncrypt, setBase64,
      setTrueColor, setCursor.

    - Encrypt and cursor settings now default to on.

    - CSS changes:
        - VNC_status_bar for input buttons switched to a element class.

        - VNC_buttons split into VNC_buttons_right and
          VNC_buttons_left

        - New id styles for VNC_settings_menu and VNC_setting

Note: the encrypt, true_color and cursor, logging setting can all be
  set on load using query string variables (in addition to host, port
  and password).

Client cursor (cursor pseudo-encoding) support has been polished and
activated.

The RFB settings are now presented as radio button list items in
a drop-down "Settings" menu when using the default controls.

Also, in the settings menu is the ability to select between alternate
style-sheets.

Cookie and stylesheet selection support added to util.js.

Instead of relying on FABridge AS -> JS event delivery, we just use
the events to notify JS of pending data. The message handler then
calls the AS readSocketData routine which sends back an array of
the pending WebSocket frames.

There is still a minor bug somewhere that happens after the first
connect where the web-socket-js throws an "INVALID_STATE_ERR: Web
Socket connection has not been established". But, Opera is now usable
and we should be able to drop the packet sequence numbering and
re-ordering code.

Another minor issue to better support Opera is to move JS script
includes to the <head> of the page instead of after the body.

Now working under Arora 0.5.

But not Konqueror 4.2.2 (WebSockets never connects).

IE support with excanvas still pending.

Also, allow 'include/' to be overridden in VNC_uri_prefix.

Move DOM manipulation into include/default_controls.js and update
vnc.html to use it.

Add an example vnc_auto.html which automatically connects using
parameters from the query string and doesn't use default_controls.js.

Reorder functions in vnc.js to put external interface functions at the
top of the RFB namespace.

- Instead of onload override, move to RFB.load function that takes
  a parameter for the target DOM ID. This allows the user to have
  their own onload function.

- Add "VNC_" prefix to all element ID names. Only create DOM elements
  if they don't already exist on the page, otherwise use the existing
  elements.

- Move all styling to separate stylesheet.

- Use list model for control styling.

On the client side, this adds the as3crypto library to web-socket-js
so that the WebSocket 'wss://' scheme is supported which is WebSocket
over SSL/TLS.

Couple of downsides to the fall-back method:

    - This balloons the size of the web-socket-js object from about 12K to 172K.

    - Getting it working required disabling RFC2718 web proxy support
      in web-socket-js.

    - It makes the web-socket-js fallback even slower with the
      encryption overhead.

The server side (wsproxy.py) uses python SSL support. The proxy
automatically detects the type of incoming connection whether flash
policy request, SSL/TLS handshake ('wss://') or plain socket
('ws://').

Also added a check-box to the web page to enable/disabled 'wss://'
encryption.

Query string variable 'b64encode' determine if wsproxy b64 encodes the
results. Variable 'seq_num' determines if sequence numbers are
prepended. This way, sequence numbers are only used with the flash
WebSocket proxy.

- All state/status updates go through updateState routine which
  updates the status line also.

- Old firefox (and opera) don't support canvas createImageData, so use
  getImageData as replacement.

- Add console.warn and console.error stubs so that firefox without
  firebug doesn't crap out.

- If no WebSockets then error if no flash or if URL is location (flash
  will refuse to load the object for security reasons).

- web-socket-js is from http://github.com/gimite/web-socket-js. It is
  a flash object that emultates WebSockets.

Unfortunately, events (or packets) from the web-socket-js object can
get re-ordered so we need to know the packet order.

- So wsproxy.py prepends the sequence number of the packet when
  sending.

- If the client receives packets out of order it queues them up and
  scans the queue for the sequence number it's looking for until
  things are back on track. Gross, but hey: It works!

- Also, add packet sequence checking to wstest.*