Add description for non-US keys on keycode.h

tmk_core/common/keycode.h

@@ -214,7 +214,7 @@ enum hid_keyboard_keypad_usage {
     KC_LBRACKET,
     KC_RBRACKET,        /* 0x30 */
     KC_BSLASH,          /* \ (and |) */
-    KC_NONUS_HASH,      /* Non-US # and ~ */
+    KC_NONUS_HASH,      /* Non-US # and ~ (Typically near the Enter key) */
     KC_SCOLON,          /* ; (and :) */
     KC_QUOTE,           /* ' and " */
     KC_GRAVE,           /* Grave accent and tilde */
@@ -264,7 +264,7 @@ enum hid_keyboard_keypad_usage {
     KC_KP_9,
     KC_KP_0,
     KC_KP_DOT,
-    KC_NONUS_BSLASH,    /* Non-US \ and | */
+    KC_NONUS_BSLASH,    /* Non-US \ and | (Typically near the Left-Shift key) */
     KC_APPLICATION,
     KC_POWER,
     KC_KP_EQUAL,