Remove redundant method
Change how email headers are passed into `send()`

Now accepts `headers` dictionary rather than using the unused `kwargs`.
Update docs
Missing ellipsis in docs

[ci skip]
Tweak docstring on `send`
Turn off travis email notifications
Explain behaviour of DEFAULT_FROM_EMAIL

[ci skip]
Typography!

[ci skip]
Update setup.py
Go badge crazy!

[ci skip]
Merge pull request #10 from incuna/clear-redundancy

Headers, docs, and reduncancy