Minor fixes for .arclint file

Summary:
Minor fixes for the .arclint file. Specifically:

• Don't explicitly lint excluded paths (they are already excluded globally)
• Set the xhpast.php-version and xhpast.php-version.windows configuration (this should have been done in D9593, but wasn't)
• Sort .arclint linters alpahbetically

Test Plan: N/A

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9803