chore(validate-commit-msg): commit msg validation

validate-commit-msg is a node script that can verify commit messages.
Installation:
- cd <project dir>
- cd .git/hooks
- ln -s ../../app/Resources/validate-commit-msg.js commit-msg

See also https://docs.google.com/document/d/1QrDFcIiPjSLDn3EL15IJygNPiHORgU1_OOAqWjiDU5Y/edit