- Decrease requirements to build in SLE/Leap:
* Werkzeug from 0.15.0 to 0.14.1
* passlib from 1.7.2 to 1.7.1
* psycopg from 2.8 to 2.7.4
* python-dateutil from 2.8.0 to 2.7.3
* simplejson from 3.16.0 to 3.13.2
* pytz from 2018.9 to 2018.3
pgadmin has this tendency to just follow the latest versions
instead of properly specify required versions.

- Update to 4.21
- New features
* Added search object functionality.
* Added LDAP authentication support.
* Added support for parameter toast_tuple_target and parallel_workers
of the table.
* Added support of Packages, Sequences and Synonyms to the
Schema Diff.
* Added an option to prevent a browser tab being opened at startup.
- Bug fixes
* Ensure that the start and end date should be deleted when clear
the selection for pgAgent Job.
* Fixed calendar opening issue on the exception tab inside the
schedules tab of pgAgent.
* Fixed an issue where the autovacuum_enabled parameter is added
automatically in the RE-SQL when the table has been created
using the WITH clause.
* Fixed generated SQL when any token in FTS Configuration or any
option in FTS Dictionary is changed.
* Fixed tab key navigation issue for parameters in table dialog.