[merge request] Some *librep* patches

[Teika Kazura <teika lavabit com>]

Hi. Please merge my branch of librep which has some doc changes.

* New section on module alias.
* That add-hook always add a new element, even if it's already present.
  in-hook-p doc.
* Misc doc.


Regards,
Teika (Teika kazura)