Fix assortment of bugs

karaage/datastores/ldap_datastore.py: Make sure we remove any group
assignments before deleting account, as they will remain otherwise.

karaage/machines/models.py: Make sure person is added to project
when creating new account.

karaage/machines/models.py: When deactivating account, don't remove
person from project.

karaage/people/models.py: Clear all groups when deactiving person.

karaage/projects/utils.py: Remove NOP save operation.

karaage/people/views/user.py: project_set renamed to projects.

Change-Id: I214d66d5d0c3ffdff8a5e50612553e2dbf3593b2