Fixed issues with MxSS RGB functionality (#3341)

* Added basic MxSS support

* Fixed split RSHFT for ISO layouts

* Updated readme.md for MxSS

* Added initial support for individual control of front RGB LEDs

* Changed RGBLED color selection to work using hue and saturation rather than RGB
Added code for LED state change on layer change

* Avoid needing an entire 8 bits to store the brightness value

* Added custom keycodes, along with their handlers

* Added EEPROM storage for front LED config

* Fixed up ability to use QMK Configurator and updated readme.md

* Applied suggested changes from pull request: https://github.com/standard/standard/issues/452

Updated name in license descriptions
Updated layouts to snake case
Corrected mistakes in info.json
Updated layer_colors to a weak attributed array in mxss.c

* Defined a new safe range for custom keycodes in keymap.c

* Fixed up issues with front LED

Fixed LEDs not always updating in indicator mode
Added support for the other RGBLIGHT modes in RGB mode

* Attempted fix for ISO layouts for QMK configurator

keyboards/mxss/mxss.c

@@ -113,6 +113,7 @@ void led_set_kb(uint8_t usb_led) {
         setrgb(0, 0, 0, &fleds[0]);
     }
 
+    rgblight_set();
 	led_set_user(usb_led);
 }
 
@@ -182,6 +183,7 @@ void fled_mode_cycle(void)
     
     // Update stored config
     eeprom_update_conf();
+    rgblight_set();
 }
 
 void fled_val_increase(void)
@@ -194,6 +196,7 @@ void fled_val_increase(void)
     
     // Update stored config
     eeprom_update_conf();
+    rgblight_set();
 }
 
 void fled_val_decrease(void)
@@ -206,4 +209,5 @@ void fled_val_decrease(void)
     
     // Update stored config
     eeprom_update_conf();
+    rgblight_set();
 }