R1:50331016f718

Modernize commit message tips

Summary: Ref T2222. Fully modernizes these tips. No callsites remain for the old methods.

Test Plan: `grep`

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2222

Differential Revision: https://secure.phabricator.com/D8457