Add django-registration-redux app

This required renaming our "registration" app, to avoid conflicting app
names.

Since only the login views were left once Django Registration views were
removed, I decided to name the app "login"
Add basic templates.

The registration templates were taken from Django Registration Redux's
sample templates.
Remove Django Sites framework.

django-registration-redux and auth.contrib will use the domain name
from the request, which works well enough and is also better for
development.
Change collected static directory to a more obvious name
Remove lint
Fix the Django Debug Toolbar
Use unique email address form for signup.

Also:
Split login/urls.py into a package and move registration urls there.
Fix running the test suite through manage.sh

Apparently the DiscoverRunner needs to be run from the project directory.

Since the Django docs generally show manage.py being used from the
directory it is in, I just changed manage.sh to always run from /opt/app
Use core.User for the auth user model.

Unique email addresses are verified in a full clean method, instead of
with `unique=True` so that we can subclass AbstractUser instead of
AbstractBaseUser.

Also adds `blank=True` to `requested_individual_mapping_at` to allow null
values to pass `full_clean`
Switch to filebased email backend for development
Remove references to site.name
Merge pull request #74 from maurizi/django-registration

Django registration
Add support for Gunicorn/Nginx

This changeset makes Gunicorn the application server for Django across
environments. In addition, Upstart handles launching the Gunicorn worker
pool and Nginx reverse proxies requests to it.

It is also important to note that when the application is provisioned in
the development and test environments, the Gunicorn `--reload` flag is
used. This provides automatic Gunicorn worker reloads when code changes
occur. I tested application reloading by making source code changes via
the Vagrant shared folder and worker PIDs changed as expected.

For more discussion, see: https://github.com/azavea/nyc-trees/pull/71
Enabling debugging support in development

In addition, I set `timeout` to 30 minutes and lowered it to 60 in the
`else` because the ELB terminates requests at 60 seconds anyway.
Remove references to `runserver`
Move gunicorn configuration to config file

This will make it easier to use the same config in multiple places
Add proof of concept script for gunicorn debugging
static -> collected_static (for now)
Move scripts to folder
Merge pull request #73 from azavea/feature/unicorn-nginx

Add support for Gunicorn/Nginx