Squashed 'tmk_core/' changes from d5c5ac6..8da1898

Squashed 'tmk_core/' changes from d5c5ac6..8da1898

8da1898 Merge remote-tracking branch 'flabbergast/chibios'
f0fdd8a ChibiOS: update instructions.md.
24dd0b5 ChibiOS: update mk to match chibios/master.
cdee266 Merge branch 'develop' into chibios
221663c Fix signatre of layer state change hooks
5a364cb Merge branch 'hotfix-chibios' into develop
af664cd Merge branch 'newapi' into develop
04feeaa Clean hook codes
0ca106d Fix code and table in hook.txt
714d418 Add hook document from njbair's work
b715129 Chibios: add default location for chibios-contrib.
fb3a323 Merge branch 'master' into newapi
8b7fbbd Merge branch 'master' into develop
e49851a Chibios: add default location for chibios-contrib.

git-subtree-dir: tmk_core
git-subtree-split: 8da189851ba83b9bb46a4290cd76b7b7fef6134e