Allow multiple device types compiled in at the same time. Renamed _IRR_USE_LINUX_DEVICE_ to _IRR_USE_X11_DEVICE_, added missing platform for Windows CE. Currently only tested in Linux (X11, SDL, console)

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2513 dfc29bdd-3216-0410-991c-e03cc46cb475