Also fixed DarwinEQEnqueue to match changes to the callback
And also use dpmsstubs.c rather than copying the code into darwin.c
(cherry picked from commit 4c5c30a4be)
General code cleanup, whitespace, dead code removal, added missing prototypes.
Made Xquartz come to foreground later in startup, so it doesn't appear for Xquartz -version
(cherry picked from commit 36922e8ff4)