Allows to find out which class a meshbuffer has.
I used the same kind of style as ISceneNode::getType. So using four CC codes and virtual functions (instead of type variable).
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6330 dfc29bdd-3216-0410-991c-e03cc46cb475
Usually something like __IRR_SOME_GUARD_INCLUDED__ replaced by IRR_SOME_GUARD_INCLUDED.
Removing underscores at the end wasn't necessary, but more symmetric (probably the reason they got added there as well).
While this touches every header it shouldn't affect users (I hope).
Also a few whitespace changes to unify whitespace usage a bit.
And a bunch of spelling fixes in comments.
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6252 dfc29bdd-3216-0410-991c-e03cc46cb475