Better ignores for coverage report.
Switched message class to EmailMultiAlternatives.
First attempt at HTML template.
Added a check that attach_alternative was called.
Documented the html_template_name attribute.
Added a way to disable HTML messages through settings.
Mentioned HTML messages in changelog.
Fixed customization docs.
Gittip -> Gratipay
Updated test requirements description.
Acknowledged sendwithus and added Apache 2.0 license.
Fixed manifest.