Do not echo messages from printer twice when in loud mode

Add debug option to menu

As this is now part of the standard interface, it's pointless
to list it as possible extension code.

In a source code repository, all sources should be visible,
including those meant to be hidden at runtime.

In verbose mode (self.p.loud = True), the code actually sending
the G-code line prints this, too, so this was a duplicate.

Making these visible should help users to find out what's going
on on unexpected printer behaviour.

No new functionality.

fix custom button drag and drop being broken, with different strategy (1px size) to hide the drag-drop targets when not in use

Make crash in estimation code not block file load.
Diable web interface by default.

printcore - send the initial M105 using _send instead of send_now

send_now can't be used until the printer is online.

Exerimental: missing colons on if statements

Check whether printer is online when calling send()

Add optional wait timeout in milliseconds to printcore send, send_now

Fixed python-n00b error

make send_now check that the printer is online before talking to it

webinterface.py compatibility with Python 2.6 

Added web interface

PHP parser

Added a little parser for the XML status returned by pronterface.

xml format fixed