People expect to be able to upload files to s3 using standard
locations for files.
Providing an action plugin that effectively rewrites the `src`
key to the result of finding such a file is a great help.
Tests added, and IAM permissions corrected
* Add aws_s3 integration tests for multipart GET operations
* Make multipart test platform-specific
* Use YAML anchors to simplify passing credentials
* Run tests on Linux and MacOSX
* Replace pause in integration tests with until.
Use resource prefix instead of generating a random number
Only try to delete keys if they exist
* Add alias to tests
* trying to delete a nonexistent bucket should not fail
* Improve error handling for deleting s3 bucket
* Allow successful deletion
* Add test for deleting a nonexistent bucket
rename integration test target from s3 to aws_s3
