Add Will to the authors

Thanks @willkg for all your help!
Add a __version__

The docs' conf.py wants it, and it's handy to have anyway.
Remove the useage

It's all in the README
Remove usage, add writing_plugins

Also add the project name.
Update the API docs, fix hacking section
Update the way to run subsets of tests
Move and update configuration docs
Replace installation with configuration
Rewrite of the writing_plugins docs
Add @mythmon and @lonnen to AUTHORS.rst

Regardung PR #33
Nix silly typo
Typo'd the name of the class
Add Will to the authors

Thanks @willkg for all your help!
Add a __version__

The docs' conf.py wants it, and it's handy to have anyway.
Remove the useage

It's all in the README
Remove usage, add writing_plugins

Also add the project name.
Update the API docs, fix hacking section
Update the way to run subsets of tests
Move and update configuration docs
Replace installation with configuration