PostgreSQL: don't use `regconfig` and `GENERATED` column anymore /!\ pgsql schema needs to be updated /!\ /!\ Minimal PostgreSQL required version is back to 9.5 /!\ `regconfig` is using system table, and `pg_upgrade` can't handle that, causing trouble when moving to a new major version of PostgreSQL. To work around this, the `data_fts_cfg` column type in `items` has been changed from `regconfig` to `text`. GENERATED column can't be used with type casting to `regconfig`, so the data_fts column is now generated with a trigger. As a result, the minimal requirement of PostgreSQL 12 is not necessary anymore.

b2149e448465d54e39bb8892ba9ded3313510738 idavoll-0.5.0
e289636ccc4f9e3690879aaf7b9bb5f2674c3fc8 idavoll-0.7.3
560b6cdc50b20d7590a70b0311d4781e3296c589 0.1.0
232002e132dbf9c7563d9f78f4b5e2bcdc2764de 0.1.1
642dffb9d6f1e7b2e7d5e9cb6ba17b6950fdf0bb 0.2.0
0861da6975b57dcaa1c69b2833232fe191346f87 0.3.0