Fix tlsclient (#30)

* fix npe in handshake

* fix tls client

examples/tlsclient.nim

@@ -3,7 +3,7 @@ import pkg/[chronos,
             chronicles,
             stew/byteutils]
 
-import ../ws/ws
+import ../ws/ws, ../ws/errors
 
 proc main() {.async.} =
     let ws = await WebSocket.tlsConnect(

ws/ws.nim

@@ -549,7 +549,7 @@ proc initiateHandshake(
   except CatchableError as exc:
     raise newException(
       TransportError,
-      "Cannot connect to " & $transp.remoteAddress() & " Error: " & exc.msg)
+      "Cannot connect to " & $address & " Error: " & exc.msg)
 
   let
     requestHeader = "GET " & uri.path & " HTTP/1.1" & CRLF & $headers