Add whitefox/billypython keymap (#4374)

* Add keyboards/whitefox/keymaps/billypython

Cloned from vomindoraan/qmk_firmware

* Customize keymap for Linux

keyboards/whitefox/keymaps/billypython/config.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#define FORCE_NKRO
+
+#undef  IS_COMMAND
+#define IS_COMMAND() (keyboard_report->mods == (MOD_BIT(KC_LSFT) | MOD_BIT(KC_RCTL)))
+
+#define MAGIC_KEY_LAYER0_ALT1  BSLS
+#define MAGIC_KEY_BOOTLOADER   ESC
+
+#define MOUSEKEY_DELAY              50
+#define MOUSEKEY_INTERVAL           15
+#define MOUSEKEY_MAX_SPEED          4
+#define MOUSEKEY_TIME_TO_MAX        50
+#define MOUSEKEY_WHEEL_MAX_SPEED    1
+#define MOUSEKEY_WHEEL_TIME_TO_MAX  50
+
+#define PERMISSIVE_HOLD
+#define TAPPING_TERM    200
+#define TAPPING_TOGGLE  2