Small fixes

Here are some small fixes for the client:

* Return the entire response from check client. This gives clients access to other important response fields, such as `score`.
* Add all arguments to `send_feedback`.  This lets clients send author IP, type, etc.
* Do not verify keys on client instantiation. Doing this adds extra requests that are unnecessary and limits the testability of mocking out the mollum client in tests.

I tried to keep the same style of comments and code.  Let me know if you have any feedback or would like other changes.