[Keyboard] Add "Uno" (#10579)

* Add all files

* Update keyboards/uno/config.h

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/uno/config.h

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/uno/rules.mk

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/uno/keymaps/default/keymap.c

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/uno/keymaps/default/keymap.c

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/uno/info.json

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/uno/readme.md

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update readme.md

Co-authored-by: Joshua Broekhuijsen <j.broekhuijsen@gmail.com>
Co-authored-by: Joel Challis <git@zvecr.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

keyboards/uno/info.json

@@ -0,0 +1,13 @@
+{
+    "keyboard_name": "Uno",
+    "keyboard_folder": "uno",
+    "url": "https://www.reddit.com/r/mechmarket/comments/gyijm7/gb_uno/",
+    "maintainer": "Snipeye",
+    "width": 1,
+    "height": 1,
+    "layouts": {
+      "LAYOUT": {
+        "layout": [ {"x": 0, "y": 0 }]
+      }
+    }
+  }