add support for automatic expression pedal pause of MIDI out until position of pedal passes the previously saved position

[sean-e]

When expression pedals are reassigned by loading a patch, do not send expression pedal MIDI until the current position of the pedal passes/picks up the previous pedal position saved when the patch was last active.

If the actual pedal position differs from the saved position of a just loaded patch, there will be no MIDI sent out until the pedal is moved to the saved last active position.