improve integration tests and add test cases

[Guslington]

Improve integration tests

the test cases require AWS resources setup and torn down each time, it might be a good idea to do this with cloudformation so we can launch it before running the test cases. It is also then much easier to cleanup at the end.

Test cases

• [x] s3 bucket is created with bucket policy and public settings disabled

for each of the resources [rds, rds_cluster, docdb, ebs, ec2ami]

• [x] create backup
• [x] share backup with 2nd aws account
• [x] pull shared backup in 2nd aws account
• [x] cleanup backup
• [x] cleanup backup in 2nd aws account