Async support

[llebout]

Hello,
As far as I can tell, this can block as it uses the sync rust-postgres crate.
Is there any chance to make this asynchronous?
Thank you

[sfackler]

Yep, I definitely plan to have a tokio-postgres version.

[llebout]

@sfackler Cool! AFAICT it doesnt seem like much effort.

[nw0]

Hi @sfackler, I'm happy to do this but need some clarification:

1. Errors: From<Error> is no longer implemented for Errorin postgres 0.18 and tokio-postgres. I'm inclined to say that ergonomically, a tokio_postgres::error::Error or postgres::error::Error is ideal, otherwise wrap in a postgres_large_object::Error type.
2. Should the interface for this crate be sync or async?

This seems like fairly straightforward code. I guess an alternative idea is to put a large_object feature into the parent crates?