(packaging) Add raring to the default cows list

Raring will be released near the end of April, so this commit adds it to the
list of cows to build against.
(packaging) Remove f16 from mocks to build as it is EOL

Fedora 16 went EOL 02-12-2013, so this commit removes it from the mocks to be
built against.
Merge pull request #427 from haus/update_cows_mocks

Update cows mocks
Merge branch '1.7.x'

* 1.7.x:
  (packaging) Remove f16 from mocks to build as it is EOL
  (packaging) Add raring to the default cows list