RexBarker

Results 5 issues of RexBarker

### Mask issue I had one technical issue... in OpenCV4, the masks read with "cv2.IMREAD_UNCHANGED" converts RGB encoded masks into np.bool types with insufficient channels. This causes many problems later....

Extended basic gwy.objects definition to include GwySurface, GwyBrick, GwyGraphModel, and GwyGraphCurveModel classes. Examples of usage updated in the README.rst file. This was tested on GwySurface and GwyGraphModel/CurveModel objects and seems...

Allows the current table "grouping" definition to be exported with the grid. This allows for python-side methods to recognize the grouped state of the table - Added 'groups' export to...

This PR allows the update of the grid export when the user sorts the table - this is a configurable option and is disabled by default: `sync_on_sort = False`

This change allows the rows to be exported as displayed in the table. This considers the following: - only sorted rows are taken (as previous implementation) - sorting order of...