Resolve note on/off pairs in MidiModel.
Add channel field to Parameter (for associating a channel with a CC list).
Add channel selector to 'add controller automation' dialog.
Write out note and CC MIDI events with proper channel.
git-svn-id: svn://localhost/ardour2/branches/3.0@3085 d708f5d6-7413-0410-9779-e7cbd77b26cf