Merged revisions 2349:2403 from 1.5 branch. Added defines for version handling, added method to check for drivers. Fix bugs in Joystick handler, filename handler, and byteswap.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2439 dfc29bdd-3216-0410-991c-e03cc46cb475