Default to "True" and "False" for bool options.

Summary:
Rather than throwing if we don't `setOptions()`, let's just default to `true`
and `false`.

Test Plan:
Removed a `setOptions()` call temporarily and saw options default to
`true` / `false`.

Reviewers: epriestley, btrahan, chad

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T2255

Differential Revision: https://secure.phabricator.com/D4368