Add MutePad keyboard (Handwired) (#16590)

* Add MutePad keyboard

* Update info.json and readme

* Move mutepad to handwired folder

* Address PR comments

keyboards/handwired/mutepad/mutepad.h

@@ -0,0 +1,19 @@
+// Copyright 2022 JoshwJB (@JoshwJB)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "quantum.h"
+
+/* This is a shortcut to help you visually see your layout.
+ *
+ * The first section contains all of the arguments representing the physical
+ * layout of the board and position of the keys.
+ *
+ * The second converts the arguments into a two-dimensional array which
+ * represents the switch matrix.
+ */
+#define LAYOUT(K00, K01, K02, K03) \
+    {                              \
+        { K00, K01, K02, K03 }     \
+    }