remove all MIDI-specific editing modes by making standard work either at object level...

remove all MIDI-specific editing modes by making standard work either at object level or within (e.g. notes, etc) ; make tool buttons proxies for GtkActions ; internal sends have their own BufferSet now, instead of using Session ones; don't make internal sends to the monitor bus active when added to the Route

git-svn-id: svn://localhost/ardour2/branches/3.0@5434 d708f5d6-7413-0410-9779-e7cbd77b26cf