Making katello build on Fedora 18

Hello all!

This patch is necessary to make Katello building on Fedora 18. It contains two workadounds. One for sass plugin require (bug in sass upstream) and I am also disabling apipie generation temporary until upstream rebase on Rails 3.2. I have introduced nodoc option, when defined, doc generation is skipped.

@inecas please remove the TODO and define once you test it please.

It's green, see you tomorrow with Fedora 18 nightly build! Let's start playing with runtime .-)

http://koji.katello.org/koji/taskinfo?taskID=22760