OS X: there is no CFRunLoop

[07151129]

This has following implications:

1. Display configuration change callback cannot be handled (see Patch: fix broken temperature setting on Quartz #385)
2. CoreLocation events cannot be handled, so e.g. if user location changed, it is ignored.

[jonls]

Thanks, this is known issue. Fixing this would, unfortunately, require a complete reorganization of the core of Redshift.