Set used variable
Warn against usage of nowdoc

Summary: Also include binary hash in the version.

Test Plan: New unit test.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D4535
Fix PHT linter

Summary: Variables in strings and concatenation lists.

Test Plan:
New unit tests.

  preg_match('/^((?>[^$\\\\]*)|\\\\.)*$/s', str_repeat('a', 1e6));

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D4540
Merge branch 'master' of http://github.com/facebook/arcanist