Added Settings page

With:
  * Target whitelist using regular expressions.
  * Target blacklist using regular expressions.
  * Global scan limit -- Amount of active scans at any given time.
  * Per scan limit -- Amount of active scans at any given time per user.
Removed fade effect from tabs
Settings now have tabs (only Scan atm)
namespaced the Settingss CSS
Settings.max_running_scans_per_user => Settings.per_user_scan_limit
User profiles are now visible to other Users
Added support for Scan Groups