[Keymap] Dactyl Manuform computer scientist's layout with split RGB enabled (#7519)

* Added my Dactyl Manuform layout

* Added my Dactyl Manuform layout

* finalized key layout, added reset code, no LED yet

* finalized key layout, added reset code, no LED yet

* enabled RGB backlight

* enabled RGB backlight

* enabled RGB backlight

* supporting split rgb

* supporting split rgb

* supporting split rgb

* added media controls

* allowing ctrl/command to fallthrough from mouse layer so we can ctrl scroll to zoom in/out

* addressed PR comments, and make a couple last minute adjustments to the layout, to add in the Forwards Delete keycode

* decreased brightness even more

keyboards/handwired/dactyl_manuform/5x6/keymaps/squirrel/config.h

@@ -0,0 +1,43 @@
+/*
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+
+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/>.
+*/
+
+
+#pragma once
+
+
+#define USE_SERIAL
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+//#define EE_HANDS
+
+// Mouse
+#undef MOUSEKEY_INTERVAL
+#define MOUSEKEY_INTERVAL       15
+#undef MOUSEKEY_TIME_TO_MAX
+#define MOUSEKEY_TIME_TO_MAX    60
+#undef MOUSEKEY_WHEEL_MAX_SPEED
+#define MOUSEKEY_WHEEL_MAX_SPEED   	3
+
+// RGB backlight
+#undef RGB_DI_PIN
+#define RGB_DI_PIN D3
+#undef RGBLED_NUM
+#define RGBLED_NUM 30
+#define RGBLIGHT_ANIMATIONS
+#define RGBLIGHT_LIMIT_VAL 95
+#define RGBLIGHT_SPLIT