Merge remote-tracking branch 'origin/feature/8584_Refl_gui_save_module'
Refs #8677. Changed the way validation is done.

Added an additional "preparation" state which is when file search is
done if necessary.
Refs #8677. Set appropriate cursor while waiting.

So that user is aware that something is happening.
Merge branch 'feature/8677_muon_seq_run_validation' into develop