system tests for policies
tests for multiple policy execution
Changed teardown to delete groups
removed delete servers script
more tests
fixed lint error
started delete_events
deleting based on policy_id
Merge branch 'master' into delete_schedule_event
delete_events takes list of policy ids

also, removed few unnecessary setup in tests
using params instead of expanding cql in code
values dict should not have ':'
Real delete one webhook
policies system test's reviews incorporated
Merge pull request #221 from rackerlabs/policy_system_tests

Policy system tests (ready for review)
Real delete one policy and all its webhooks
Real delete scaling group
addressed ying's comments
Merge branch 'master' into delete_schedule_event
using string.format