Add keyboard: ACR60 (#1999)

* base acr60 keyboard folder created

* mitch acr60 keymap updates, documentation

* latest keymap updates

* slight modifications to layer switching

keyboards/acr60/acr60.c

@@ -0,0 +1,28 @@
+#include "acr60.h"
+#include "led.h"
+
+void matrix_init_kb(void) {
+  // Keyboard start-up code goes here
+  // Runs once when the firmware starts up
+  matrix_init_user();
+  led_init_ports();
+};
+
+void matrix_scan_kb(void) {
+  // Looping keyboard code goes here
+  // This runs every cycle (a lot)
+  matrix_scan_user();
+};
+
+void led_init_ports(void) {
+  // Set caps lock LED pin as output
+  DDRB |= (1 << 2);
+  // Default to off
+  PORTB |= (1 << 2);
+}
+
+void led_set_kb(uint8_t usb_led) {
+  // Code for caps lock LED as reported by the OS
+  // Set this per keymap, instead of globally
+  led_set_user(usb_led);
+}