VisualUnitTest: Fix lack of window termination through WM close
device_info: Fix couple bugs that potentially segfault

* Fix ver output of SDL2 compiled & linked vers.

* Fix crash on Windows for OpenGL ver (output is still broken, but
at least it doesn't crash..)
Add conditional build macros for libRocket

* Building of libRocket's Lua integration features is now disabled
by default.