OSX only: the Apple key now is a normal modifier in code, so can be

detected as others, LR_COMMANDKEY

Unline previous commit, Apple key doesnt map to control anymore, but is
handled separate where needed. Now only for undo (Apple-Z)

source/blender/include/mydevice.h

@@ -186,6 +186,7 @@
 #define	ENDKEY		170
 
 #define UNKNOWNKEY	171
+#define COMMANDKEY	172
 
 /* **************** BLENDER QUEUE EVENTS ********************* */