azavea/OTM2 — pull request #129 by ahinz (2013-08-01 21:59:32+00:00)
Title: Create a system user and use it for creating users

Since only the system itself creates, updates and deletes user this
commit updates the user model to automatically provide a system user
when saving objects.

It also provides a management command to create a new system user

The default system user is set to '-1', does not belong to any
instances, and has its login disabled.
intermd cmt