close: Implement CloseNow

Closes #384

close.go

@@ -102,6 +102,15 @@ func (c *Conn) Close(code StatusCode, reason string) error {
 	return c.closeHandshake(code, reason)
 }
 
+// CloseNow closes the WebSocket connection without attempting a close handshake.
+// Use When you do not want the overhead of the close handshake.
+func (c *Conn) CloseNow() (err error) {
+	defer errd.Wrap(&err, "failed to close WebSocket")
+
+	c.close(nil)
+	return c.closeErr
+}
+
 func (c *Conn) closeHandshake(code StatusCode, reason string) (err error) {
 	defer errd.Wrap(&err, "failed to close WebSocket")
 

conn.go

@@ -147,6 +147,12 @@ func (c *Conn) close(err error) {
 	if c.isClosed() {
 		return
 	}
+	if err == nil {
+		err = c.rwc.Close()
+		if err == nil {
+			err = errors.New("WebSocket closed abnormally")
+		}
+	}
 	c.setCloseErrLocked(err)
 	close(c.closed)
 	runtime.SetFinalizer(c, nil)