LMMS/lmms — pull request #866 by diizy (2014-06-18 21:46:22+00:00)
Title: Fix stuck notes on notestacking

Add a check to notestacking so we don't add subnotes to nph's that are already released (this can happen with very rapid notes, eg. sliding the mouse accross the gui piano).
Also a fix in nph to prevent silent master notes getting stuck "playing" without getting deleted.