support new rest API

Based on recent communications from Akamai they are going to stop supporting the SOAP interface on June 1st.

This PR is fairly extensive overhaul to switch over to the rest API. There are a number of breaking changes so this should come with a major version bump. Here are some of the highlights:

- Drop Django code. It felt a little out of place to me, and I think a cleaner solution will be to have the Django plugin leverage this code
- Addition of unittests wihch have the API calls mocked so they run quickly and don't require valid credentials for testing. Added some documentation to a development.md for instructions on how they can be run.
- Pylint and PEP8 cleanup
- Dropped the WSDL file and suds dependency so there is no SOAP interaction any more.
- Liberal use of custom exception classes