Changes to import properly and work with Django 1.5+
Changes to allow URL Shortener to work

1. Convert model to use TextField so the length of the URL is not limited to 200.
2. Remove _uniq=[0-9]* from URL
3. Change response from /s/ to be plain text instead of HREF
4. Add button into Dashboard UI
5. Put window.location.origin on returned location in composer and dashboard UI.
6. Add window.locaiton.origin on Direct URL in dashboard UI as well.