[Feature Request] Panning law

[sezero]

From Thomas Neumann (@neumatho):

I have a little request you may put on your todo list, namely support of panning law, specially for FastTracker 2. I found this you may use as reference: https://forum.openmpt.org/index.php?topic=6084.0 http://weaselaudiolib.sourceforge.net/#panning_law https://modarchive.org/forums/index.php?topic=3517.0