Add requirements.txt for pip

Just a stop-gap measure until I have an actual setup.py written up, probably
once I have documentation in a more manageable state.
Update templates to the new Pilot changes
nitpicky: reformat AUTH_METHODS config
Pull more of the shared functionality into the base Auth* classes

Reduces subclass imports, and reduces code duplication.
Merge branch 'master' into document-all-the-things

* master:
  Pull more of the shared functionality into the base Auth* classes
  nitpicky: reformat AUTH_METHODS config
  Update templates to the new Pilot changes
  Add requirements.txt for pip
Add the start of a half-decent intro
Add user documentation for submitting and reviewing

Some (most?) of the images will have to be redone later to match revised UI in the future.