Add premade layouts for Numpad 4x4, Numpad 5x4, Ortho 5x4, and Planck MIT (#3139)

Fix EOF on Planck MIT layout.json

Cleanup ortho_5x4 layout.json

layouts/default/ortho_5x4/default_ortho_5x4/keymap.c

@@ -0,0 +1,38 @@
+#include QMK_KEYBOARD_H
+
+#define _______ KC_TRNS
+#define XXXXXXX KC_NO
+
+enum custom_keycodes {
+    KC_P00 = SAFE_RANGE
+};
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+    if (record->event.pressed) {
+        switch(keycode) {
+            case KC_P00:
+                // types Numpad 0 twice
+                SEND_STRING(SS_TAP(X_P0) SS_TAP(X_P0));
+                return false;
+        }
+    }
+    return true;
+};
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  [0] = LAYOUT_ortho_5x4(
+    TG(1),   KC_PSLS, KC_PAST, KC_PMNS, \
+    KC_P7,   KC_P8,   KC_P9,   KC_PPLS, \
+    KC_P4,   KC_P5,   KC_P6,   KC_PPLS, \
+    KC_P1,   KC_P2,   KC_P3,   KC_PENT, \
+    KC_P0,   KC_P00,  KC_PDOT, KC_PENT  \
+  ),
+
+  [1] = LAYOUT_ortho_5x4(
+    _______, _______, _______, _______, \
+    KC_HOME, KC_UP,   KC_PGUP, _______, \
+    KC_LEFT, XXXXXXX, KC_RGHT, _______, \
+    KC_END,  KC_DOWN, KC_PGDN, _______, \
+    KC_INS,  XXXXXXX, KC_DEL,  _______  \
+  ),
+};

layouts/default/ortho_5x4/layout.json

@@ -0,0 +1,5 @@
+["","","",""],
+["","","",""],
+["","","",""],
+["","","",""],
+["","","",""]

layouts/default/ortho_5x4/readme.md

@@ -0,0 +1,3 @@
+# ortho_5x4
+
+    LAYOUT_ortho_5x4