Sync with all revisions up to FreeBSD date.1:1.72 (ru), notably:

Sync with all revisions up to FreeBSD date.1:1.72 (ru), notably:
- Add the new standard EXIT STATUS section where appropriate.
  Sort standard sections in the (documented) preferred order.
  Author: ru, date.1:1.71
- Give the most awesome example of how to parse the output of date
  back into Epoch time. Author: alfred, date.1:1.67
- Better SYSNOPIS. Author: green, date.1:1.63
- Lots of minor man page cleanups by ru.
- Bump man page date.

Submitted-by: Sarunas Vancevicius <svan_at_redbrick_dot_dcu_dot_ie>