* [cloud][tests] Create fixtures for using placebo to test boto3-using modules
* Use pytest's importorskip instead of manually skipping on missing deps
* Fix imports in cloudformation module
* Delete unused code
* Add maybe_sleep fixtures to speed up recorded test runs
* Build basic placebo-CFN tests
* Commit placebo recordings of basic stack operations
* Add placebo to test-requires
* Allow unit tests to run regardless of environment by setting a default region
* Use explicit relative import for Python 3 compat
* Use __name__ attribute that works on Python 2 and 3
