Flip around default parameters in beginScene and setRenderTarget in a way that causes less deprecated warnings, but still does the same in general. That avoids some troubles with function resolution when only first 2 parameters got set (otherwise needed explicit casts to u16).
Use new image->getData in example to avoid warnings.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@5205 dfc29bdd-3216-0410-991c-e03cc46cb475