More flexible MRC

[Mr Arkadin]

Simple idea but I think it would be quite nice to have the MRC in its current format, but with selectable controls. Instead of just the rotary pot one could select the control to be a rotary, a fader, a switch (momentary or latch) or a blanking panel (to get rid of those pointles knobs with "n/a" on them). This would give some functions a better context (on/off switches on pots doesn't make much sense) and would create more interesting GUIs without it being a fully skinnable deal (something I'm sure CW want to stay clear of).