Fix ctrl+(shift)+tab shortcut key not working on OS X after recent bugfix to
interact better with system shortcuts.

This is a special shortcut for switching between views and does not get
delivered directly to our view when we pass it through the application key
event handling path. We only have a single OpenGL view, so there's no need to
pass it on to the application, instead just interpret it directly.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56728 954f8c5b-7b00-dc11-b283-0030488c597c
Remplace bunch of annoying ifdefs in tracking.c with a libmv-capi_stub.cc

Makes code in tracking.cc much easier to understand and modify,
without worring to breck compulation with Libmv disabled.

It is still possible compilation will break due to libmv-capi
changes, but that's not happening so much often.



git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56729 954f8c5b-7b00-dc11-b283-0030488c597c