Add monitor "Rotate" option taking one of "normal", "left", "inverted" or
"right". However, because initial mode selection is made before the screen
is completely initialized, we cannot create the shadow pixmap object at this
point. Pend the shadow pixmap creation until the block handler.
Note that this code is not completely functional yet.
This code comes from the intel driver, so there's no history in this tree.
As the crtc/output-based mode selection code uses ddc, the ddc and i2c
modules have been merged into the server. Attempts to load them are safely
ignored now.
