Add setuid bit to pam-escalate-helper when it's installed.
Rename EscalateHelperCheckUsername() to EscalateHelperIsUserAllowed().
Make sure EscalateHelperDoAction() is never called without a matching EscalateHelperHandleStart(), and make EscalateHelperHandleStart() support multiple calls even though we don't support it yet.
Fix style issues in escalate_helper.c.
Fix style issue in escalate_helper_test.c.
Explained error handling better for a broken pipe when reading a message.