Refs #8535.
Merge branch 'feature/8528_slice_event' into feature/8535_gui_slicing_support
Refs #8535. Reorganize the SANSRunWindow layout
Refs #8535. Introduction of widget for slicing support

SANSRunWindow
Refs #8535. Apply the slices for the reduction SANSRunWindow
Refs #8535.
Merge branch 'feature/8528_slice_event' into feature/8535_gui_slicing_support
Merge remote-tracking branch 'origin/feature/8535_gui_slicing_support'