Time and region selection now follow undo.
Fix region muting undo bug.
Fix delete clicked regionview undo.
Revert #include reduction.
Rename stuff.
Help detect some errors wrt begin/commit reversible_command order.
Fix mouse mode not changing on selection undo.
Revert bogus mouse mode fix - store editor state instead. This is slow.
Set editor state via a SelectionMemento (tm) instead.
Add editor zoom to SelectionMemento, remove some leftover cruft.
Time and region selection now follow undo.
Fix region muting undo bug.
Fix delete clicked regionview undo.
Revert #include reduction.
Rename stuff.
Help detect some errors wrt begin/commit reversible_command order.
Fix mouse mode not changing on selection undo.
Revert bogus mouse mode fix - store editor state instead. This is slow.
Set editor state via a SelectionMemento (tm) instead.
Add editor zoom to SelectionMemento, remove some leftover cruft.
Merge branch 'selection_undo' of https://github.com/nmains/ardour into selection_undo

Conflicts:
	gtk2_ardour/editor_ops.cc
	gtk2_ardour/midi_region_view.cc