Add Gitter support

vendor/github.com/mrexodia/wray/transport.go

@@ -0,0 +1,21 @@
+package wray
+
+import (
+	"errors"
+)
+
+type Transport interface {
+	isUsable(string) bool
+	connectionType() string
+	send(map[string]interface{}) (Response, error)
+	setUrl(string)
+}
+
+func SelectTransport(client *FayeClient, transportTypes []string, disabled []string) (Transport, error) {
+	for _, transport := range registeredTransports {
+		if contains(transport.connectionType(), transportTypes) && transport.isUsable(client.url) {
+			return transport, nil
+		}
+	}
+	return nil, errors.New("No usable transports available")
+}