* Update Shippable integration test groups.
* Update integration test group aliases.
* Rebalance AWS and Azure tests with extra group.
* Rebalance Windows tests with another group.
* New module: ec2_vpc_egress_igw
* minor pep8 fix and doc update
* add test dir and files
* add tests for gateway module
* fix up return documentation per review
* remove HAS_BOTO3 stuff as it is handled in AnsibleAWSModule per review
* fix an error with failure message and add custom handler for non-existent vpc ID
* add additional tests and update tests per review
* ignore errors on clean up tasks
* update module copyright to newer format
* fix exception handling since BotoCoreError doesnt have response attribute
* actually fix exception handling this time so it works with Py3 as well
