Backlight abstraction and other changes (#439)

* redoes matrix pins, abstracts backlight code for B5,6,7

* slimming down keyboard stuff, backlight breathing implemented

* don't call backlight init when no pin

* cleans up user/kb/quantum calls, keyboard files

* fix pvc atomic

* replaces CHANNEL with correct var in breathing

* removes .hexs, updates readmes, updates template

* cleans-up clueboards, readmes to lowercase

* updates readme

quantum/template/keymaps/default/keymap.c

@@ -1,6 +1,3 @@
-// This is the canonical layout file for the Quantum project. If you want to add another keyboard,
-// this is the style you want to emulate.
-
 #include "%KEYBOARD%.h"
 
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
@@ -28,3 +25,20 @@ const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt)
       }
     return MACRO_NONE;
 };
+
+
+void matrix_init_user(void) {
+
+}
+
+void matrix_scan_user(void) {
+
+}
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  return true;
+}
+
+void led_set_user(uint8_t usb_led) {
+
+}