[Keyboard] Add Keybage folder for RadPad (#9745)

* [Keyboard] Initial Keybage/RadPad firmware

* [Keyboard] RadPad apply pull request feedback

- Change `LAYOUT_***_Encoders` to `LAYOUT_***_encoders` in <keyboard>.h
- Remove bootloader comments and unnecessary build options from rules.mk
- Use `LTO_ENABLE`
- Remove empty config.h from default keymap
- Remove trailing ` \` from keymap

* [Keyboard] RadPad fix info.json

- Change `LAYOUT_***_Encoders` to `LAYOUT_***_encoders` in info.json

* [Keyboard] Add host LED status to OLED display

* [Keyboard] Use LAYOUT_4x4_encoders, not LAYOUT

* [Keyboard] Use LAYOUT_4x4_encoders, not LAYOUT

* [Keyboard] Remove DESCRIPTION from config.h

keyboards/keybage/radpad/radpad.c

@@ -0,0 +1,17 @@
+/* Copyright 2020 Brandon Schlack
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "radpad.h"