[Keyboard] Add bthlabs/geekpad (#4840)

* Hello, GeekPad!

* Fixed formatting in `README.md`.

keyboards/bthlabs/geekpad/keymaps/default/keymap.c

@@ -0,0 +1,24 @@
+/* Copyright 2019-present Tomek Wójcik <contact@bthlabs.pl>
+ *
+ * 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 QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  [0] = LAYOUT( /* Base */
+    KC_F1, KC_F2, KC_F3,
+    KC_MEDIA_REWIND, KC_MEDIA_PLAY_PAUSE, KC_MEDIA_FAST_FORWARD,
+    KC_AUDIO_MUTE, KC_AUDIO_VOL_DOWN, KC_AUDIO_VOL_UP
+  ),
+};