- CGUIEnvironment::loadGui - loading a gui into a target-element no longer messes up when the gui-file contained guienvironment serialization.
- Improve IGUIEnvironment::loadGui documentation.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4272 dfc29bdd-3216-0410-991c-e03cc46cb475