[Keyboard] Add Glitch (#16444)

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

keyboards/p3d/glitch/readme.md

@@ -0,0 +1,24 @@
+# Glitch
+
+Hotswap RGB Alice-style with OLED and Rotary Knob
+
+-   Keyboard Maintainer: matthewdias
+-   Hardware Supported: Glitch PCB
+-   Hardware Availability: https://p3dstore.com
+
+Make example for this keyboard (after setting up your build environment):
+
+    make p3d/glitch:default
+
+Flashing example for this keyboard:
+
+    make p3d/glitch:default:flash
+    
+## Bootloader
+
+Enter the bootloader in one of 2 ways:
+
+* **Bootmagic reset**: Hold down the top left and plug in the keyboard
+* **Physical reset button**: Briefly press the button on the top of the PCB
+
+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).