FI-508: Prevent html rendering in responses

[Jammjammjamm]

The CGI.escapeHTML method doesn't work if the html is escaped unicode. This branch unescapes all escaped unicode in responses so that html is not rendered when displaying responses.

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• This pull request describes why these changes were made
• Internal ticket links to this PR
• Internal ticket is properly labeled (Community/Program)
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• Code diff has been reviewed for extraneous/missing code
• n/a Tests are included and test edge cases
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• Code is maintainable and reusable, reuses existing code and infrastructure
  where appropriate, and accomplishes the task's purpose
• The tests appropriately test the new code, including edge cases
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Reviewer 2:

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• Code is maintainable and reusable, reuses existing code and infrastructure
  where appropriate, and accomplishes the task's purpose
• The tests appropriately test the new code, including edge cases
• You have tried to break the code