Note: Currently we still will have the font-texture for CGUIFont's in the cache afterward.
But that needs a more general mechanims that allows cleaning up textures easier when the last one has been removed.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@3465 dfc29bdd-3216-0410-991c-e03cc46cb475