Fix keymap for new actions

Merge branch 'action_refine'

Fix keymap of hhkb for new actions

Fix doc/keymap.md for new actions

Fix keymap of gh60

Fix ACT_MODS action and switch_default_layer command

Add file action_code.h

Fix doc/keymap.md

Fix ACTION_LAYER macros

Rename file layer_switch to action_layer

Refine ACT_LAYER and ACT_LAYER_TAP

- Remove ACT_LAYER_BITOP

Remove ACT_KEYMAP and ACT_OVERLAY

- Remove ACT_OVERLAY
- Rename ACT_KEYMAP to ACT_LAYER
- Add ACT_LAYER_BITOP

Fix BOOTLOADER_SIZE setting

Refine README.md

Merge branch 'action_tapping'

Add action_tapping.[ch] for refactoring

Merge branch 'matrix_scan_fix'

Fix debouncing on gh60, hbkb, macway

Merge branch 'suspend_fix'

Add sleep LED test command