This change adds services.pgbouncer.settings option as per [RFC 0042]
and deprecates other options that were previously used to generate
configuration file.
In addition to that, we also place the configuration file under
environment.etc to allow reloading configuration without service
restart.
[RFC 0042]: https://github.com/NixOS/rfcs/blob/master/rfcs/0042-config-option.md
these changes were generated with nixq 0.0.2, by running
nixq ">> lib.mdDoc[remove] Argument[keep]" --batchmode nixos/**.nix
nixq ">> mdDoc[remove] Argument[keep]" --batchmode nixos/**.nix
nixq ">> Inherit >> mdDoc[remove]" --batchmode nixos/**.nix
two mentions of the mdDoc function remain in nixos/, both of which
are inside of comments.
Since lib.mdDoc is already defined as just id, this commit is a no-op as
far as Nix (and the built manual) is concerned.
