Avoid argument lookup ambiguity in swap when used in combination with stl....

Avoid argument lookup ambiguity in swap when used in combination with stl. Using same trick as boost now and use 2 different template parameters in it.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@3281 dfc29bdd-3216-0410-991c-e03cc46cb475

include/irrMath.h

@@ -162,10 +162,14 @@ namespace core
 	}
 
 	//! swaps the content of the passed parameters
-	template <class T>
-	inline void swap(T& a, T& b)
-	{
-		T c(a);
+	// Note: We use the same trick as boost and use two template arguments to 
+	// avoid ambiguity when swapping objectsof an Irrlicht type that has not 
+	// it's own swap overload. Otherwise we get conflicts with some compilers 
+	// in combination with stl. 
+	template <class T1, class T2>
+	inline void swap(T1& a, T2& b)
+	{
+		T1 c(a);
 		a = b;
 		b = c;
 	}