templates/public/home.html:
- removed cookiecutter copy
- added a small explanation of the site
templates/users/checkout.html:
- added placeholder html template
templates/nav.html:
- added nav link to members' vav bar
user/views.py:
- added render_template_or_404(url): to wrap render_template
- changed def members() to point to users/members
- changed def checkout() to point to users/checkout