Adding monitoring tests and their required changes

Changes made to lib/bin/rackspace.rb and lib/fog/rackspace.rb were required in
order to allow the tests to actually run. Changes to
lib/fog/rackspace/monitoring.rb were made in an effort to get failure tests to
run without the error that I am purposefully creating causing the test to fail.
Now catching errors correctly, all tests succeed
Catching errors correctly, all tests succeed.