* Converted ec2_metric_alarm to boto3. Added treat_missing_data option.
* Handle potentially non-existent alarm keys in ec2_metric_alarm module
* Add treat missing data to ec2_metric_alarms wth some tests
Continues the work of #23407
* Clean up ec2_metric_alarm main test playbook
* fix test suite and sanity checks
* more fixes for sanity tests
* fixes to ec2_metric_alarms requested in code review
* import ClientError from botocore, catch generic ClientError
* more fixes from review
drops extra dict in argument spec and set_facts for aws access
* Fix pep8 blank line issue
* switch to fail_json_aws, add idempotency test
* fix under indented continuation
* remove unsupported alias
* Add group to ec2_metric_alarm aliases
* Put alarm prefix before resource prefix to match aws-terminator pr 63
* Add type for treat_missing_data
