Adds menu entries to each EQ/filter and tracks for transposing by semitones.
Supplies a “live-transpose" slider to transpose either only one eq/filter device, all eqs/filters in a track, in the signal flow or in the whole song.
Picture the signal flow roughly as a tree structure, starting with the master or a send track as the root node (with possible parallel routing, too) until the leaf nodes, which can be either the playing tracks or even the instrument dsp lanes.
