How to allow use of IntoSocketAddrs with UDP types

[Nemo157]

Part of my thoughts with rustasync/runtime#101 and #3 was that runtime::net::UdpSocket::send_to could be deprecated and replaced with async_datagram::AsyncDatagramExt::send_to (or become an inherent method that just forwards to the trait method).

Unfortunately that would lose out on being able to use impl IntoSocketAddrs for the destination address. Is there some way a change to the AsyncDatagram trait, the extension trait, and/or the implementation for runtime::net::UdpSocket could allow using this?