Support M82/M83 for relative E

Clean up echoed firmware lines, connect info.

Presently, when you connect to a printer using pronsole, one sees
something like:

uninitialized>start
uninitialized>Printer is now online
uninitialized>echo: External Reset
printer>Marlin 1.0.0 RC2
...

With a few carriage returns and some string hackery, we clean up
the output so that one sees:

No port specified - connecting to /dev/ttyACM0 at 115200bps
start
Printer is now online
External Reset
Marlin 1.0.0 RC2

Much cleaner!

Clean up the monitor command.

The monitor command now:

* Has more pythonic code
* Limits precision of progress elements (12.3% instead of 12.347812...%)
* Uses a carriage return to have print progress replace the previous
  progress line.

For example:

Monitoring printer, use ^C to interrupt.
Updating values every 5.000000 seconds.
Print progress: 0.3%

Previously, the line "Print progress: 0.3%" was "Print progress: 0.2%",
etc.

Fancy configurable prompts!

* Prompts are now generated based off of string templates,
  for example: "%(bold)sT:%(extruder_temp_fancy)s %(progress_fancy)s
  >%(normal)s "

* We have a dictionary of prompt string templates for different
  situations.

* We have bold support for the prompt.

* We have extruder temperature support for the prompt.

* We have progress support for the prompt.

gcoder updated

Fix Ctr-C and Ctr-D behavior.

Temp prompt

We replace the cmdloop function with a slightly modified version
to achieve standard unix shell behavior on keyboard interupts and EOF.

In order to do this, we consolidate handeling of printer status
with a Status class. The status class is updated by recvcb.

This has the side effect of simplifying the implementation of gettemp.

We also detect whether there is a heated build platform or not, and
don't display info about it if there isn't.

Prompt is now generated by a promptf() call for every cmdloop iteration.

updated gcoder

Conflicts:
	pronterface.py

added gcoder from another project. using gcoder to calculate dimensions and used filament

fixed measurement calculation for X and Y axis

Conflicts:

	pronsole.py

Add the GNU GPL text as the licese itselfs demands

GUI creation split