Fix bug with multiple SetPixelFormat calls.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4917 dfc29bdd-3216-0410-991c-e03cc46cb475
Added support for fullscreen window manager on linux. Patch provided by Deve.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4918 dfc29bdd-3216-0410-991c-e03cc46cb475
Fixed issues with setViewPort method under OpenGL. (reported by anontypist)

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4919 dfc29bdd-3216-0410-991c-e03cc46cb475
Added OGLES1 support for FB device.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4920 dfc29bdd-3216-0410-991c-e03cc46cb475