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

keyboards/hhkb/hhkb.h

@@ -1,10 +1,7 @@
 #ifndef HHKB_H
 #define HHKB_H
 
-#include "matrix.h"
-#include "keymap.h"
-//#include "backlight.h"
-#include <stddef.h>
+#include "quantum.h"
 
 #define KEYMAP(                                                                \
     K31, K30, K00, K10, K11, K20, K21, K40, K41, K60, K61, K70, K71, K50, K51, \
@@ -24,7 +21,4 @@
     { K70, K71, K72, K73, K74, K75, K76, KC_NO }                               \
 }
 
-void matrix_init_user(void);
-void matrix_scan_user(void);
-
 #endif