server: A general solution for handling MAXIMUM_ALLOWED access right has been implemented so remove the workarounds.

The gl viewport origin is the lower left corner of the window, in d3d
it is the upper right corner. This is corrected when setting the
viewport. However, when we are doing offscreen rendering, this is
reversed. So do not flip the viewport origin when rendering offscreen.

Except with fbos, it is not possible to remove the depth stencil
buffer from the opengl frame buffer, so when the d3d app sets a NULL
depth stencil disable all states that work with the depth stencil
buffer.

This helps performance a bit because the function does not have to
wait for the 2nd read to finish before returning. Only do that if we
have an aux buffer to mess with for free though.

Plain OpenGL does not provide any signed pixel formats, so the
unsigned GL_RGB is used for loading perturbation data into pixel
shaders that use texbem. For correct loading, the signedness has to be
considered.

Add tests for these cases.

secur32: NTLM - don't bother nul terminating the password string as nothing relies on it being nul terminated.

pointers in the SEC_WINNT_AUTH_IDENTITY structure than the
corresponding Length fields say the pointers hold.

wineps.drv: Return correct values for DESKTOPHORZ/VERTRES since they are used to setup the visible region.

(spotted by Alessandro Pignotti).

winex11.drv: Do not ignore the keysyms assigned to a group switch, it leads to side effects like missing KeyRelease events.

Only objects that have been registered for a class context that matches 
the requested class context should be returned.