MusE v0.8.1 released

MusE has been updated to v0.8.1; it is basically a bug-fix release for a note-off bug that crept into 0.8.

Changes:

• Added next/prev marker, keyboard shortcut.
• Added LASH support; this also means that ladcca is no longer supported.
• Reverted fix for silent softsynths, synths were not silenced upon [stop].
• Added Motif-Rack idf from europeen.