Add back session buttons. Fixes #246
Refactor home index view

All the content was in the layout. The layouts responsibility it
to hold shared content.

- Moved all non shared content into index.html.erb
Merge branch 'master' into add_sign_in_and_sign_out_buttons
Merge pull request #247 from codeforamerica/add_sign_in_and_sign_out_buttons

Add sign in and sign out buttons