Support for YMDK NP21 (#2316)

* ymdk_np21 initial support

Base support of ymdk_np21 - based on jj40. Full grid layout

* Update README.md

Replacing description.

* Adding YMDK NP21 to comunity list.

Adding YMDK NP21 to community supported list.

keyboards/ymdk_np21/keymaps/default/keymap.c

@@ -0,0 +1,47 @@
+#include "ymdk_np21.h"
+#include "action_layer.h"
+
+#define _NP 0
+#define _BL  1
+
+enum custom_keycodes {
+  NP = SAFE_RANGE,
+  BL
+};
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+/* Qwerty
+ * ,-----------------------------------------.
+ * |   0  |   1  |   4  |   7  | NUM  | ESC  |
+ * |------+------+------+------+------+------|
+ * |   .  |   2  |   5  |   8  |   /  | TAB  |---,
+ * |------+------+------+------+------+------|USB|
+ * |  DOT |   3  |   6  |   9  |   *  | BS   |---'
+ * |------+------+------+------+------+------|
+ * | Enter| Enter|   +  |   +  |   -  | FN   |
+ * `-----------------------------------------'
+ */
+[_NP] = KEYMAP( \
+  KC_KP_0,     KC_KP_1,     KC_KP_4,    KC_KP_7,    KC_NUMLOCK,     KC_ESC,    \
+  KC_DOT,      KC_KP_2,     KC_KP_5,    KC_KP_8,    KC_KP_SLASH,    KC_TAB,    \
+  KC_KP_DOT,   KC_KP_3,     KC_KP_6,    KC_KP_9,    KC_KP_ASTERISK, KC_BSPACE, \
+  KC_KP_ENTER, KC_KP_ENTER, KC_KP_PLUS, KC_KP_PLUS, KC_KP_MINUS,    MO(_BL)     \
+),
+/* Qwerty
+ * ,---------------------------------------------.
+ * | BL_BRTG |        |         |        |   |   |
+ * |---------+--------+---------+--------+---+---|
+ * |         | BL_OFF | BL_TOGG | BL_ON  |   |   |---,
+ * |---------+--------+---------+--------+---+---|USB|
+ * |         |        |         |        |   |   |---'
+ * |---------+--------+---------+--------+---+---|
+ * | BL_DEC  | BL_DEC | BL_INC  | BL_INC |   |   |
+ * `---------------------------------------------'
+ */
+[_BL] = KEYMAP( \
+  BL_BRTG, _______, _______, _______, _______, _______, \
+  _______, BL_OFF,  BL_TOGG, BL_ON,   _______, _______, \
+  _______, _______, _______, _______, _______, _______, \
+  BL_DEC,  BL_DEC,  BL_INC,  BL_INC,  _______, _______  \
+)
+};