R1:afe9a1a914f5

Delete commit template

Summary: This is part of propagating the workflow `git commit -m 'One liner' && arc diff`.

Test Plan: Searched for references to this file.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D2675