Playhead
Added a customisable and movable playhead that draws a line guide for showing current position. You can free to hide/display it by setting showsPlayhead
property on timetable.
Also, you can inform about position changes by new delegate method midiTimeTableView(_ midiTimeTableView: MIDITimeTableView, didUpdatePlayhead position: Double)
.
And, you can set the position of playhead by timetable.playheadView.position = 4.25
to update from code.