Added management command to add users. Can be used locally and on heroku.

Moved test user name and password to env variables.

Changed error handling in server view functions to follow what's now
on property frontend.

Updated template to handle json structure directly.

Updated test. Moved test json to own module.
Add missing files
Added tests for http and connection errors
Actually don't need the test user env variables.

Just create users using manage.py (which can be run on heroku as well).
Update config.py
Merge pull request #6 from LandRegistry/refactor

Refactor