Meira Refactor (#14566)

* clean up keyboard header files

* use #pragma once include guard
* convert tabs to spaces
* remove redundant #include statements
* update revision references to main header (`../meira.h` -> `meira.h`)

* refactor default keymap

* use LAYOUT as layout macro reference
* use enum statement for layer indexes; make layers contiguous
* use four-space indent
* update keycode grid alignment

* update layout macro aliases

* move layout macro aliases to info.json
  * alias KEYMAP to LAYOUT_ortho_4x12 so the user keymaps don't have to be edited

* touch up meira.h

There's no Planck MIT layout reference here.

* add copyright headers

* workaround patch for grahampheath keymap

The `matrix_init_kb()` function in `meira.c` calls `backlight_set()`, but the grahampheath keymap disables Backlight to make space for Audio, causing the firmware to fail to compile.

This commit wraps the `backlight_set()` call in an ifdef statement, so the call is excluded if Backlight is disabled.

* clean up rules.mk inline comments

* re-order rules.mk settings

* clean up readme.md

* correct link to keyboard image
* change metadata section to unordered list
* spelling corrections
* update make instructions and Docs links

[Docs] update Japanese translation of feature_backlight.md (#14403)

* update feature_backlight.md translation

* update file based on comments

[Docs] update Japanese translation of feature_advanced_keycodes.md (#14309)

* update feature_advanced_keycodes.md translation

* update file based on comments

[Docs] update Japanese translation of isp_flashing_guide.md (#13700)

* update isp_flashing_guide.md translation

* update isp_flashing_guide.md translation

* correct url

* trim remaining merge identifier

[Docs] update Japanese translation of feature_leader_key.md (#13669)

* update feature_leader_key.md translation

* update file based on comments

* update text based on comments

[Docs] update Japanese translation of one_shot_keys.md (#13656)

* update one_shot_keys.md translation

* update one_shot_keys.md translation

* correct paramter for function

* add change of #13754

[Keyboard] Bkf (#14534)

Co-authored-by: Ryan <fauxpark@gmail.com>

Remove BLUETOOTH_ENABLE from keyboard-level rules.mk (2021-09-22) (#14567)

* Remove BLUETOOTH_ENABLE from keyboard-level rules.mk (2021-09-22)

* update keyboards/handwired/slash/rules.mk per fauxpark

[Keyboard] Fix default keymap for Draytronics Elise V2 keyboard (#14562)

[Keyboard] Disable console on Smallkeyboard (#14561)

[Keyboard] Version 2 of Draytronics Elise Keyboard + ISO Keymap Change (#14253)

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

[Keyboard] add kk980 keyboard (#14436)

[Keyboard] Fix jkb65 compile issues (#14554)

[Keyboard] Fix font file for Ein 60 Keyboard (#14553)

[Keyboard] Add Dango40 (#14437)

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Swiftrax <swiftrax@gmail.com>
Co-authored-by: Swiftrax <swiftrax@github.com>

[Keyboard] Add Free Willy Keyboard (#14394)

Co-authored-by: Ryan <fauxpark@gmail.com>

[Keyboard] 0-Sixty: Splits kb config into base and underglow (#14384)

Co-authored-by: Drashna Jaelre <drashna@live.com>

[Keyboard] Add support for XT8x (#14440)

Co-authored-by: Drashna Jaelre <drashna@live.com>

[Keyboard] fixed one of the unicode drawings of the layout in dz60.h (#14482)

[Keyboard] Add JadooKB JKB65 RGB (#14525)

Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Drashna Jaelre <drashna@live.com>