Bug 1103052 - Remove traces of RBTools; r=mconley

We previous added support for RBTools in bug 943747 and bug 945577. Now
that we have MozReview, this functionality is next to useless. MozReview
is the future. So, we remove the old RBTools code.

DONTBUILD (NPOTB)

--HG--
extra : rebase_source : 2b307c31a5c484cb0bd785f582e3c248c3cb11da