Rename "PhabricatorHash::digest()" to "weakDigest()"

Summary: Ref T12509. This encourages code to move away from HMAC+SHA1 by making the method name more obviously undesirable.

Test Plan: `grep`, browsed around.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T12509

Differential Revision: https://secure.phabricator.com/D17632

src/applications/auth/controller/PhabricatorAuthTerminateSessionController.php

@@ -16,7 +16,7 @@ final class PhabricatorAuthTerminateSessionController
       $query->withIDs(array($id));
     }
 
-    $current_key = PhabricatorHash::digest(
+    $current_key = PhabricatorHash::weakDigest(
       $request->getCookie(PhabricatorCookies::COOKIE_SESSION));
 
     $sessions = $query->execute();