* Add CHANGELOG from existing tags.

First release under the Prometheus Community organisation.

* [CHANGE] Update build to use standard Prometheus promu/Dockerfile
* [ENHANCEMENT] Remove duplicate column in queries.yml #433
* [ENHANCEMENT] Add query for 'pg_replication_slots' #465
* [ENHANCEMENT] Allow a custom prefix for metric namespace #387
* [ENHANCEMENT] Improve PostgreSQL replication lag detection #395
* [ENHANCEMENT] Support connstring syntax when discovering databases #473
* [ENHANCEMENT] Detect SIReadLock locks in the pg_locks metric #421
* [BUGFIX] Fix pg_database_size_bytes metric in queries.yaml #357
* [BUGFIX] Don't ignore errors in parseUserQueries #362
* [BUGFIX] Fix queries.yaml for AWS RDS #370
* [BUGFIX] Recover when connection cannot be established at startup #415
* [BUGFIX] Don't retry if an error occurs #426
* [BUGFIX] Do not panic on incorrect env #457

Signed-off-by: Ben Kochie <superq@gmail.com>