Summary: Ref T4195. Even though we use `svnlook` in the hook itself, I need this query elsewhere, so provide it and merge the classes into one which does the right thing.
Test Plan:
- Used `reparse.php` to reparse messages for Git, SVN and Mercurial commits, using `var_dump()` to examine the commit refs for sanity.
- Used `reparse.php` to reparse changes for an SVN commit.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4195
Differential Revision: https://secure.phabricator.com/D7800
