added more template options

The PHP client now supports everything under the “Templates” section of
our API docs
fixed formatting in tests file

The tests file was formatted all wonky, it’s all better now.
better names, post -> put
updated README and other changes

Updated to make it so html isn’t optional when creating new templates
Fixed as per Troy's CR
fixed typo and tests
derp forgot endpoint
should not have c&p'd that test...
derp
fixed v.numbering and update_template_version

C’mon travis!
Fixed — finally.
Merge pull request #25 from sendwithus/feature/finer-template-control

Feature/finer template control