Proof of concept mechanism for hiding questions related to ineligible benefits

From #51:
> Screening seem to be working as intended for the MVP release. Some post-mvp improvements for hiding questions based on benefits 'in play' is recommended. Some questions that are benefit-specific will still appear after a benefit has already been determined ineligible. For example "Have you continuously owned and occupied your property as your primary residence since at least July 1, 2014?" still appears when LOOP has been marked as already enrolled. This question does not pertain to any of the other benefits

The issue names no files, tests, or entry points. Start by locating the screening logic and how benefits already determined ineligible are represented; done means benefit-specific questions such as the LOOP property question no longer appear after LOOP is ineligible, while unrelated questions remain.

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