Feature/unittesting

Just something for you to have a look at @fiorix

There's a few things in this PR, which is not finished, but should start the conversation at least:
1. A unit testing tool for testing handlers. So far it handles both instant and deferred responses.
2. Started adding unit tests for cyclone itself. Thus far only the http client and the new test case class + client.
3. A requirements file - I've included mock in there, but maybe it shoudn't be there.

To run the tests simply run `trial cyclone`

This obviously starts to deal with this issue: https://github.com/fiorix/cyclone/issues/132 

Let me know what you think mate! If you're keen then I'll keep on with adding unit tests to the lib and document how to write unit tests for cyclone handlers.