Separate environment requirement files.

New requirements folder with per environment requirements.
Heroku ready.

Added parameters to meet a Heroku ready application.
Procfile ready
Heroku Ready, Skeleton.

Production database, unicorn ready deploy with 3 workers.
Changes in the README file with new instructions.
Change environment variable.

Set the correct environment variable for the primary heroku postgresql database.
Bump to version 0.4.