When stopping on redirect, show a full stack trace
Summary: Ref T4140. Provide more debugging information so we can figure out what's going on with redirect loops.
Test Plan: {F83868}
Reviewers: chad, btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T4140
Differential Revision: https://secure.phabricator.com/D7620