[LMMS-devel] Correction of play button problems (almost definitive)

[Alexandre A. <me...@ho...>]

Here are the patches which correct almost entirely the problems with the "play/pause" button of the song editor.
The automation editor is the only editor which still has problems.

An issue I have noticed (not related to the "play/pause" button) is that the Beat+Bassline Editor does not open if the user clicks on a Beat+Bassline pattern in the song editor but has clicked on the button to hide it before.