Remove some unnecesssary headers.
Remove some dead code that was never called or used in pbproxy.
Make use of an NSAutoreleasePool in x_init. It could potentially cause a leak
on a startup without this.
Start adding reload_preferences to the x_selection class, as well as event
handling for that.
(cherry picked from commit 602e8ba8f7ee196696bc9e3cea6ecdf3200dcf5c)
b1d0b19661