Log Message:
Update databases/pgbouncer to 1.8.1.

PgBouncer 1.8.1
===============

Fixes

- Include file `include/pam.h` into distribution tarball. This
  prevented the 1.8 tarball from building at all.

PgBouncer 1.8
===============

Features

- Support PAM authentication.  (Enable with `--with-pam`.)
- Add `paused` and `disabled` fields to `SHOW DATABASES` output.
- Add `maxwait_us` field to `SHOW POOLS` output.
- Add `wait` and `wait_us` fields to `SHOW` commands output.
- Add new commands `SHOW STATS_TOTALS` and `SHOW STATS_AVERAGES`.
- Track queries and transactions separately in `SHOW STATS`. The
  fields `total_query_time`, `avg_query`, `avg_query`, and `avg_query`
  have been replaced by new fields.
- Add `wait_time` to `SHOW STATS`.

Fixes

- Updated libusual supports OpenSSL 1.1.
- Do not attempt to use TLS on Unix sockets.
- When parsing `pg_hba.conf`, keep parsing after erroneous lines
  instead of rejecting the whole file.
- Several other hba parsing fixes.
- Fix race condition when canceling query.

Cleanups

- `auth_user` setting is now also allowed globally, not only per
  database.
- Set console client and server encoding to `UTF8`.