<ticket>#626</ticket>
<ticket>#626</ticket>

gui/application.py:
- VistrailsApplicationSingleton.init:
  Returning True after connecting to other instance hangs vistrails so we always return False
- VistrailsApplicationSingleton.message_received:
  Send critical message when write fails
- VistrailsApplicationSingleton.send_message:
  Handle correct successful message "Command Completed"
  Always disconnect from server

celiafish/VisTrails,celiafish/VisTrails,Nikea/VisTrails,minesense/VisTrails,hjanime/VisTrails,celiafish/VisTrails,hjanime/VisTrails,VisTrails/VisTrails,minesense/VisTrails,celiafish/VisTrails,Nikea/VisTrails,minesense/VisTrails,VisTrails/VisTrails,VisTrails/VisTrails,hjanime/VisTrails,hjanime/VisTrails,minesense/VisTrails,VisTrails/VisTrails,Nikea/VisTrails,VisTrails/VisTrails,hjanime/VisTrails,Nikea/VisTrails,minesense/VisTrails