Basically fixing original Bug#427 reported by MArkus Elfring.
Unfortunately there are still more defines (in IrrCompileConfig.h) which also are not nice c++
Lots of files touched for very minor cleanup *sigh*
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6253 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
Also adding some to VS2010 project file (for better project search)
Some empty line removal.
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6228 dfc29bdd-3216-0410-991c-e03cc46cb475
