Add warning that quaternion::operator* has anoter operator order than CMatrix4::operator*

Fixing it would be nice, but is probably worse. It would break users-apps in a very hidden way and 
it's too easy to work around this problem to make such an evil API-change instead.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@5071 dfc29bdd-3216-0410-991c-e03cc46cb475

include/quaternion.h

@@ -67,6 +67,7 @@ class quaternion
 		quaternion operator+(const quaternion& other) const;
 
 		//! Multiplication operator
+		//! Be careful, unfortunately the operator order here is opposite of that in CMatrix4::operator*
 		quaternion operator*(const quaternion& other) const;
 
 		//! Multiplication operator with scalar