* Update validate-modules
* Validates ANSIBLE_METADATA
* Ensures imports happen after documentation vars
* Some pep8 cleanup
* Clean up some left over unneeded code
* Update modules for new module guidelines and validate-modules checks
* Update imports for ec2_vpc_route_table and ec2_vpc_nat_gateway
* Check if EIP exists before deleting it
After deleting the NAT gateway, the EIP sometimes seems to
cease to exist afterwards. Check if it exists before deleting it.
Otherwise you get:
```
Failed to release EIP eipalloc-abdc1234: An error occurred (InvalidAllocationID.NotFound) \
when calling the ReleaseAddress operation: The allocation ID 'eipalloc-abcd1234' does not \
exist", "success": false}
```
* Fix flake8 errors with ec2_vpc_nat_gateway
Matt Martz
Will Thames
Matt Clay
Carlos E. Garcia
James Cammarata