Upgrade to Django 1.9 (backward compatible)

[dnaranjo89]

• Use post_migrate signal instead of post_syncdb (post_syncdb is deprecated since Django 1.7)
• Update import of GenericForeignKey (Moved in Django 1.7)
• Use Model._meta.model_name (Model._meta.module_name alias was removed in Django 1.8)
• Use HttpRequest.GET instead of HttpRequest.REQUEST (HttpRequest.REQUEST is deprecated since Django 1.7)

[jcreem]

This really should get pulled