feat: "messages" pgoutput option to receive messages from pg_logical_emit_message()

[darkgnotic]

Allows setting of the messages option in pgoutput starting parameters to enable receipt of messages outputted by pg_logical_emit_message.

Reference: https://www.postgresql.org/docs/current/protocol-logical-replication.html#PROTOCOL-LOGICAL-REPLICATION-PARAMS

Closes #35

[kibae]

Hi, @darkgnotic
Thank you for your contribution! Your work is much appreciated, and this merge will certainly help improve the project. We value your time and effort in making this happen. I'll be publishing the update to npm shortly.

[kibae]

@darkgnotic I have published an npm package and added you as a contributor. However, I left the public email field empty because I didn’t know your email address. If you’d like to fill it in, please provide your email address.

b0640a8#diff-7ae45ad102eab3b6d7e7896acd08c427a9b25b346470d7bc6507b6481575d519R68

[darkgnotic]

Thank you @kibae!