Print stack traces on daemon exceptions

Summary: Currently, we force daemon exceptions to STDERR but not associated traces. Force traces to STDERR too.

Test Plan: Triggered a daemon exception with --log, verified trace hit the web logs.

Reviewers: btrahan, chad

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2193

Differential Revision: https://secure.phabricator.com/D4206