Change error handling in uuid to displayname pithos path migration.
Stop migraton if it fails to retrieve a uuid/displayname.
Expose /user_catalogs service api call
Change migration scripts to use this instead of the user api call
Change feedback & user_catalogs astakos && pithos api calls
Change pithos sharing to work with account uuids
Migrate username to uuid in pithos permissions
Fix negative population in statistics table
Provide error feedback during pithos database path migration to container uuid instead of email
Update Astakos API to provider calls for retrieving uuid from the username and vice versa, extend astakos client library (snf-common) and update pithos to use uuids instead of email for account identification
Fix code formatting to conform to the PEP 8 style guide
fix nodes latest_version revision
Refs: #2675
Introduce alembic