GProgressDialog

.. in an attempt to avoid the QT 5.3.1 QProgressSialog
   bug and also put a bit of our own styling onto this
   a GC implementation of QProgressDialog

.. it has no abort button DELIBERATELY

.. not tested on OS X .. yet
GProgressBar honour Theme Flat/Mac
GProgressDialog Mac QT 5.3.1 fixups

.. being more careful with modality and mainwindow
Change 'Classic' theme

.. it needed color selections that worked better on
   a light background
Merge remote-tracking branch 'upstream/master'