Fix cloud_watch delete when the watchrule is not found.

Also start using mock instead of mox.

Change-Id: Ia3baf510ffeafc73c42da7e2830819055c244c51
Skip RSA generation during tests

Use a static key in Rackspace cloud server tests, to remove the overhead
of the SSH keys generation.

Change-Id: Ief14f034fb86e42ecbb801b9d4f82ff27fb35588
Merge "Skip RSA generation during tests"
Merge "Fix cloud_watch delete when the watchrule is not found."