Implemented hamburger menu, profile page.
Wire up home button in menu, add banner image to profile.
Implement mentions view.
Implement scrolling header in profile view.
All new required elements complete:
 - implement paging view in profile header
 - add stats to profile page
 - allow tapping on profile pictures in timeline
 - first pass at making links in tweets clickable
Add some more optional features:
 - Pulling down in profile view zooms in on the banner image
 - Links in tweets open Safari
 - Visual tweaks to hamburger menu
Added walkthrough and credit for TTTAttributedLabel.