Adding 3305 for 4key keyboards

Author: softplus

1209/3305/index.md

@@ -0,0 +1,11 @@
+---
+layout: pid
+title: 4key-keyboards
+owner: 3-Key-Ecosystem
+license: Apache 2.0
+site: https://github.com/softplus/3keyecosystem
+source: https://github.com/softplus/3keyecosystem/tree/main/4key
+---
+
+This is for my 2x2 switch USB macro-keyboards running on QMK.
+It's used by both 4key1 (single LED per key) and 4key2 (RGB WS2812B LED per key), and uses a modular base-board.