Continuing work on AssistantComposerMainForm

Many changes, and I'm not going back, so a
commit was long overdue.
Continuing to test, and correct the user interface.
Continued work on AssistantComposerMainForm

This is at last working quite well.
No known bugs (still testing).
Refactored "okay to save" to "confirm", both in
button names and functions.
Confirm and revert buttons now have a consistent
look across all forms.
Revised Reverting AssistantComposer forms

The DimensionsAndMetadata, PaletteForms and
OrnamentsSettingsForms are now reverted by
reloading from the saved file.
The notation, krystals and palettes on the main
form were already done this way.