Added missing files to setup.py

If I install Printrun via setup.py, I don't have gcoder.py and I cannot even
use pronterface.py:

Traceback (most recent call last):
  File "/bin/pronterface.py", line 46, in <module>
    import pronsole
  File "/usr/bin/pronsole.py", line 23, in <module>
    from gcoder import GCode

So I've added this to setup.py.

Also, pronsole.ico is missing, added that too (not needed at runtime, but is
usefull for desktop files)