Add third party theme

Theme is non-bootstrap so we'll need to do some wrangling of both the
css and the markup to get the best out of it.
Start customising theme
Add favicon
Add more theme elements
Style name area and panels
Tweak date styling
Apply theme to side nav
Even more nav styling
Button styling
Footer markup
Sticky footer
Fix active nav item styling

Was using descendant selector rather than direct child selector
Tweak sticky footer size
Add RSVP page title
Merge pull request #3 from exonian/feature/make-less-ugly

Make the site less ugly!