Various random tweaks made with Ned at meeting (sorry no ticket number...)

Includes:
 * UI tweaks to make home page diary take up less space
 * Colour-coded show/people/venue/society 'tags' in autocomplete
 * Converted URLs to links in news feed
Merge branch 'master' of github.com:camdram/camdram
Changed favicon to something that isn't the Symfony logo. Ned might be able to suggest something better... #19
Merge branch 'master' of github.com:camdram/camdram