fixed some problem with the TrackingParams that was caused by the conversion of Bool to Str or similar. For whatever reason the True in the Tracking Params was shown as a string rather than a Boolean.
removed the print statements
added explicit options to change the qt4 to wx and back by commenting out (TODO: find automatic identification of the working backend)
spaces instead of tabs
Merge pull request #13 from alexlib/fix_tracking_parameters_GUI

Fix tracking parameters gui