Adding PlaybackRange to the framesMode menu.
Adding PlaybackRange to the framesMode menu.

Now that we have menu items which don't map directly to enum values, we need to manage the selection menu ourselves.

Fixes #1007.

johnhaddon/gaffer,ivanimanishi/gaffer,hradec/gaffer,ivanimanishi/gaffer,hradec/gaffer,lucienfostier/gaffer,chippey/gaffer,appleseedhq/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,hradec/gaffer,boberfly/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,hradec/gaffer,ivanimanishi/gaffer,andrewkaufman/gaffer,goddardl/gaffer,cedriclaunay/gaffer,GafferHQ/gaffer,goddardl/gaffer,GafferHQ/gaffer,hradec/gaffer,andrewkaufman/gaffer,ivanimanishi/gaffer,andrewkaufman/gaffer,boberfly/gaffer,boberfly/gaffer,lucienfostier/gaffer,chippey/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,chippey/gaffer,lucienfostier/gaffer,ImageEngine/gaffer,lucienfostier/gaffer,GafferHQ/gaffer,appleseedhq/gaffer,cedriclaunay/gaffer,cedriclaunay/gaffer,chippey/gaffer,johnhaddon/gaffer,appleseedhq/gaffer,goddardl/gaffer,goddardl/gaffer,cedriclaunay/gaffer,boberfly/gaffer