Add support for 21.11.x, remove 21.6.x as ChibiOS "canceled" it. (#15435)

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Fix minor typo in Ploopy Trackball Docs (#14846)

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Flip encoder and fix weird volume behavior for Herringbone Pro (#15423)

Co-authored-by: Joel Challis <git@zvecr.com>

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Add Contender (#15403)

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

Expand rotational range for PMW3360 Optical Sensor (#15431)

Fix RESET not working for keyboards with Kiibohd bootloader (#15430)

Remove references to Makefile in keyboard-level rules.mk (#15427)

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Fix minor typo in Ploopy Trackball Mini Docs (#14845)

Merge remote-tracking branch 'origin/master' into develop

[Keymap] 3w6 helltm keymap combos (#15393)

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Add stickey4 keyboard (#15396)

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

[Keyboard] Add jolofsor folder and denial75 subfolder under QMK keyboards (#15334)

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

Merge remote-tracking branch 'origin/master' into develop

[Keyboard] Add Eternal keypad (#15413)

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

Merge remote-tracking branch 'origin/master' into develop