Revamp `TlsSocket` API

[Paul Chiusano]

TlsSocket will pick up an additional argument, the underlying Socket.

TlsSocket.close will then terminate the underlying Tls and close the Socket.

@stew also suggested that TlsSocket.create could just do the handshaking:

or TlsSocket create function could just take HostName and Port instead of Socket, and just rename terminate to close

convo in Slack

[Rúnar]

With the existence of https://share.unison-lang.org/@runarorama/tls-simple, snoozing this for now.