Properly reset global state upon library shutdown.
add some paranoid locking around WM_ConvertOptions setting and retrieval for thread safety. reset WM_ConvertOptions upon library shutdown.
missing part after _SetOptions revert. fix a possible null ptr dereference
added IBM's XMIDI format docs
Merge pull request #11 from Mindwerks/master

update my fork
Merge pull request #12 from chrisisonwildcode/master

updating branch