- added DynamicSupervisor, which starts Pleroma deps and restarts config dependent deps
- added pleroma installer, where user can configure database credentials
and pleroma config. Settings are saved into file and in database
- added versioning for in database config. New version is created from
changes which are passed to config update/delete endpoint. Every version
contains backup with all changes added through update. Versioning
supports rollbacks with N steps. With a rollback, all versions that
come after the version on which the rollback was made are deleted.
