net/py-s3transfer: Update to 0.1.1, Modernize

• Update PORTVERSION and distinfo checksum (0.1.1)
• Add LICENSE_FILE
• Document actual Python version support in a comment for later
• Patch setup.py to properly declare test dependencies and hook up the test command
• Add TEST_DEPENDS and test target for QA

https://github.com/boto/s3transfer/blob/0.1.1/CHANGELOG.rst

Approved by: Bradley Hughes <bradleythughes fastmail fm> (maintainer, via email)