www/py-requests: Update to 2.4.3

- Update to 2.4.3
- Update to USES and USE_PYTHON new world order
- Add LICENSE_FILE
- Add TEST_DEPENDS
- Update pkg-descr

Changes:

  https://github.com/kennethreitz/requests/blob/v2.4.3/HISTORY.rst


git-svn-id: svn+ssh://svn.freebsd.org/ports/head@373438 35697150-7ecd-e111-bb59-0022644237b5