Merge branch 'release/2.8.0.1' into develop
[Nereid] Migrate nereid-cms to 3.0 #3128

* Removed en_US from urls
* Modified tests to work

Project-ID: 989
Task-ID: 3128
Merge pull request #26 from uditagarwal/develop

[Nereid] Migrate nereid-cms to 3.0 #3128
[Nereid] Issue#24 Fix for Nereid CMS #3163

* Fixed the check_constraint method by using
  the right method
* Fixed selection field on Menu Item not saving
  if list is empty
* Wrote test

Project-ID: 989
Task-ID: 3163
Git Issue: https://github.com/openlabs/nereid-cms/issues/24