Consider using tokio-postgres in place of sqlx

[ValuedMammal]

And possibly renaming the crate along the lines of "bdk_postgres".

[tvpeter]

@ValuedMammal I would like to work on this.

[ValuedMammal]

Yeah it might be worth looking into. One thing to keep in mind is that this library should still work with any existing apps that use sqlx, so if moving to tokio-postgres causes any sort of dependency clash that could be a problem.

[tvpeter]

From an initial consideration, the Error::Sqlx will result in a breaking change. Except we consider returning errors from queries as Error::Sqlx.

[matthiasdebernardini]

I'm ok with that, the current error handling from sqlx is not that useful because when it fails it doesn't say which query fails, it just says the reason why. I have no problem with the error types changing.