Percussion tracks display diamonds.
Separated/fixed MIDI and audio mode menus.
CC automation modes: discrete, line.
Bar controllers follow setting (hard steps or line) on playback.
Sent CC data is always discrete (line not implemented yet).
Discrete tracks show no lines, and always show control points.
Separated ControlPoint from AutomationLine.
Added some basic information (range) to Parameter (to be fleshed out..).
git-svn-id: svn://localhost/ardour2/trunk@2123 d708f5d6-7413-0410-9779-e7cbd77b26cf
