(LUN-782) Cleaned template name

Added a clean_fields() method on the Template model which removes any extra trailing whitespace from the template name.
Added tests for template name cleaning

Added tests for checking whether any extra trailing whitespace is removed from the template name.
(LUN-782) Fixed logic bug and added more tests

Validation errors are now properly shown;
Added some more tests for checking whether template name extra trailing whitespace is properly removed.
(LUN-782) Review changes

Changed rstrip() with strip() and modified tests accordingly;
Removed some unnecessary comments.
(LUN-782) More review fixes

Removed call to clean_fields() in Template.save();
Changed tests to  reflect the new behavior;

All in all, any template added via the admin form is properly cleaned, while those added via Django ORM (e.g.: Template.objects.create([...])) are saved as they are.
Merge pull request #5 from pbs/LUN-782

LUN-782