fixes #6550 / BZ 1117952 - fix issues with changing org name which affected running db:seed

Without these changes, the user cannot change the default organization
name and re-run 'rake db:seed'.  The reason being, it would attempt
to create an organization with a label that was already in use and
the seed would fail.

In order to address this, this commit does a couple of things:
1. when creating an org, if a label is automatically generated
   and it is already in use, re-generate the label using a uuid.
2. fix an existing validation which was incorrectly comparing
   name=label, label=name, etc. during org create and update.
A user can go from having a human readable label to one that is a UUID with no way to change it. That feels like a bad interaction from a user's stand point. I wonder if we shouldn't:

1) Return the label that is invalid and prompt the user that it is invalid
2) Take the label and tack on numbers to keep the readability? e.g. Myorg -> Myorg1