Fix #73: Linkify email addresses in task descriptions.
Fix #47: Enforce a more consistent header size across the site.

This is a stopgap. Long-term we're going to need to clean up the CSS
across the site, as our less files are kind've a mess right now.

Also fixes up list spacing in task details.
Merge pull request #81 from Osmose/favicon

Fix #66: Add QMO favicon.
Merge pull request #82 from Osmose/consistent-buttons

Fix #67: Move all action buttons to be right-aligned.
Fix #22: Only show task areas with available tasks in list filter.
Update filter to include is_draft check and improve availability checks.
Fix #23: Include email address in login failure message.
Fix #32: Customize Persona popup.
Fix #36: Style site-wide messages.