Async conform support about revalidator

[markstos]

I agree. It's a fairly common pattern to validate against a database to check if a given value exists there.

[mariuszdev]

It would be very useful for me too.

[dhoomm]

waiting for async before can use it.

[ChuckPierce]

This is discouraging to see that this issue was opened in 2013 and it still isn't resolved. Async support is fundamental in node programming. I can't even use promises because the conform function can't see the returns I'm making in a .then()...this should definitely be supported

[Jason-Bellomy]

This project isn't supported much anymore. I'm guessing the people that support it are super busy, or just don't have time to do it. My team and I have just been updating the code to match what we need.

[okv]

I and my colleagues maintain fork (conform.js)[https://github.com/okv/conform.js] main features we've added - optional source modifications (apply default values to the source object, apply type casting results to the source object, etc). But we also don't have async conform function because we don't need that. But if somebody do the pr (with tests), we could accept that =)