Summary: Fixes T4276. This adds "Change is enormous" to pre-commit content rules so we can, e.g., just reject these and not worry about them elsewhere. Also, use the same numeric limits across the mechanisms so there's a consistent definition of an "enormous" changeset. Test Plan: - Set enormous limit to 15 bytes, pushed some changes, got blocked by a rule. - Set it back, pushed OK. Reviewers: btrahan Reviewed By: btrahan CC: aran Maniphest Tasks: T4276 Differential Revision: https://secure.phabricator.com/D7887