Use "closed", not "committed", in Differential
Summary: "Committed" is SVN-specific language, and confusing in Git and Mercurial. Use neutral language instead.
Test Plan: Inspection.
Reviewers: btrahan, Makinde, vrana, jungejason
Reviewed By: vrana
CC: aran
Maniphest Tasks: T909
Differential Revision: https://secure.phabricator.com/D2087