Create a script for killing __init__.php

Summary:
Maybe we should integrate it in arc liberate.
Maybe it should support non-Git repositories.
But this is all I have.

Test Plan: Run it on Arcanist and Diviner.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Koolvin

Maniphest Tasks: T1103

Differential Revision: https://secure.phabricator.com/D2566