Create Model and Collection classes.  Model classes represent an
individual entry in the database, while collections represent an entire
collection in the database.  Model methods function on the individual
entry level, updating and getting attributes of a specific entry in the
database.  Collections operate on the collection level--this is pretty
self explanatory.  Each collection has a Model class associated with it, and
when find_one or find is called, it will return Models of this class.

Right now, there are Models for users and blog posts, and collections
for the same.  Comment Models and Collections should be implemented as
well.

--Ben Attal
Add settings.py