Added SDL_GetLoadedModule to do the equivalent of GetModuleHandle/dlload(NOLOAD)

CR: Jorgen
As part of Jorgen's code review of this function I added a call to LoadLibrary so the refcounts would be consistent between Windows and Posix. Then I forgot to include the check that the thing was actually loaded and caused it to be loaded all the time.  Oops.


CR: AaronL
Fixed lost mouse button when in relative mouse warp mode and you click on the title bar, entering a modal move/resize loop.

Testing:
* Set the SDL_HINT_MOUSE_RELATIVE_MODE_WARP hint true, run testsprite2, press Ctrl-R to enter relative mode, alt tab away from the window, then click on the title bar of the window. Didn't get the mouse button release before, and we do now.

CR: Yahn + Alfred
Added SDL_DXGIGetOutputInfo which returns the adapter and output indices that are used to create DX10 and DX11 devices and swap chains on a particular display.

CR: SamL
Back out changelist 2026006
Back out changelist 1951976
Added the new function at the end so we don't break the ABI