Fix software renderer inconsistency with rest of drivers in case of invalid destination rect for draw2DImage. Now no driver will render an image in these cases.
Added a test case to check behavior of all drivers for this situation.
Fixed comparison of similar test case to support fuzzy comparison and relaxed threshold.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4143 dfc29bdd-3216-0410-991c-e03cc46cb475