Add MutePad keyboard (Handwired) (#16590)

* Add MutePad keyboard

* Update info.json and readme

* Move mutepad to handwired folder

* Address PR comments

keyboards/handwired/mutepad/readme.md

@@ -0,0 +1,33 @@
+# MutePad
+
+[MutePad Repo](https://github.com/JoshwJB/MutePad)
+
+A 3D printed under desk mounted keypad with rotary encoder, for muting applications (discord, zoom etc.) and adjusting volume.
+
+* Keyboard Maintainer: [JoshwJB](https://github.com/JoshwJB)
+* Hardware Supported: ProMicro
+* Hardware Availability: Handwired - see [MutePad Repo](https://github.com/JoshwJB/MutePad)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make handwired/mutepad:default
+
+Flashing example for this keyboard:
+
+    make handwired/mutepad:default:flash
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
+
+## Bootloader
+
+Enter the bootloader in 2 ways:
+
+* **Bootmagic reset**: Hold down the key at (0,0) in the matrix (usually the top left key or Escape) and plug in the keyboard
+* **Physical reset button**: Briefly short the ground and reset on the ProMicro
+
+## Images
+![image](https://user-images.githubusercontent.com/15612025/157335123-a76ce059-86b4-4484-9bb2-0abff8a13cc8.png)
+
+### Wiring
+![image](https://user-images.githubusercontent.com/15612025/157336673-ad348e3d-4314-4703-afe0-a43a6f73b892.png)
+![image](https://user-images.githubusercontent.com/15612025/157335150-8491553f-a7dc-462a-a6af-bc4be223b703.png)