Changed to use url parts from config file.
Changed login/logout paths.

Changed
=======

* Moved login and logout commands under account. So to login, go to
  account/login.
Added user_db variable that points to users.db.
Changed to get username/password from users.db.
Changed to return 401 error on failed login.
Added get_public_models, get_private_models.

Added
=====

* New functions:
  - get_public_models
  - get_private_models
  that get models owned by the current user and publicly-viewable
  models.

Removed
=======

* Removed function get_models. It is now the same as get_public_models.
Added context to globals when rendering pages.
Added get_username function.
Added footer with username and sign in/out link.
Changed to only get authorized models.

Added
=====

* New AuthorizationError class thrown when trying to view/edit
  a model that is not public or not owned by the current user.

Changed
=======

* get_model function now raises an error when trying to get a model
  that is the user is not authorized to get.
Changed to return 401 if getting an unauthorized model.
Changed to record username for new submissions.
Merge branch 'master' of https://github.com/csdms/wmt