Summary:
Ref T13209. This gives us a clean suite under Windows. The actual changes are a lot of miscellaneous stuff which I'll walk through inline in more detail.
The biggest change here is just rewriting some stuff like `cat`, `echo`, `sleep`, etc., in PHP. These commands either don't exist, don't work the same way, or are shell builtins (and we're now bypassing the shell) under Windows. So replace `cat ...` with `php -f cat.php -- ...` to make the tests portable.
Test Plan: No remaining test failures on Windows.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13209
Differential Revision: https://secure.phabricator.com/D19729
