User URI.encode instead of CGI::escape to compose URIs

Closes #134
Add username regexp matching

Closes #134
Merge pull request #137 from hackatron/feature/fix-user-link

Use URI.encode instead of CGI::escape to compose URIs and username validation
Merge pull request #144 from mulderp/url_for_setup

use URL for setup
Ruby 1.9.2+ compatible (RSpec tests)
Adding missing page title for comment permalink pages
use Rack for API
redis middleware