[Presence XT Editor] Allow using pedal to trigger / switch between layers

Writing Javascript is a wall to those users who aren't comfortable with programming languages. However, currently, there is no other way to directly use pedal to trigger / switch between layers. In fact, using certain CC parameters to trigger cetain samples / layers is crucial for most sampler users who create samples today. Please support this through the GUI of Presence XT Editor in lieu of asking users to write Javascripts.