Improve homepage and QA logo images.
Fix #33: Style task detail page
Fix #26: Homepage should match wireframes.
Fix #50: Hide options for starting tasks if user has already started.
Fix #20: Show feedback page after a user has abandoned a task.
Fix #58: Change task area filter empty message to "All Areas".
Fix #30: Style pagination.
Fix #72: Feedback text for completion and abondon task should match.
Fixes #71 changed color of abandon task button
Fix #65: Remove team colors on homepage.
Fix #66: Add QMO favicon.
Fix #67: Move all action buttons to be right-aligned.

Also removes some unnecessary positioning for the profile page 
navigation.
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.