Add support for self-signed certificates

config.go

@@ -1,6 +1,7 @@
 package xmpp
 
 import (
+	"crypto/tls"
 	"io"
 	"os"
 )
@@ -13,6 +14,7 @@ type Config struct {
 	StreamLogger   *os.File // Used for debugging
 	Lang           string   // TODO: should default to 'en'
 	ConnectTimeout int      // Client timeout in seconds. Default to 15
+	TLSConfig      tls.Config
 	// Insecure can be set to true to allow to open a session without TLS. If TLS
 	// is supported on the server, we will still try to use it.
 	Insecure      bool