Constructs a new secure client socket and connect it to the given host on port port. The returned Future will complete with a SecureSocket that is connected and ready for subscription.
If sendClientCertificate is set to true, the socket will send a client certificate if one is requested by the server.
If certificateName is the nickname of a certificate in the certificate database, that certificate will be sent.
If certificateName is null, which is the usual use case, an appropriate certificate will be searched for in the database and sent automatically, based on what the server says it will accept.
onBadCertificate is an optional handler for unverifiable certificates. The handler receives the X509Certificate, and can inspect it and decide (or let the user decide) whether to accept the connection or not. The handler should return true to continue the SecureSocket connection.