Create the dashboard and welcome views.

This is an initial attempt at laying the ground work for two important pages that
should evolve and change over time - the welcome page and dashboard page.
The associations for some of the data is not quite ready, as well as the activity
feeds. Those are not in here yet, but once they are ready they will be added in.

The dashboard is what an authenticated user sees. It displays the activity feed
for the cookbooks they follow and easy to find links for the cookbooks they own
and contribute to.

The welcome page is what a non-authenticated user sees. It introduces them to
what Supermarket is and highlights what they can do on Supermarket.