Pass the offer data explicitly to the feedback form

[willbarton]

The feedback form had previously acquired the offer data indirectly from the referrer URL. This change passes that data directly to the form in the form of the query string so that it can be recorded along with the message. This should fix the current issues of the referrer being blank by explicitly providing the data needed.

Checklist

• Changes are limited to a single goal (no scope creep)
• Code can be automatically merged (no conflicts)
• Code follows the standards laid out in the front end playbook
• Passes all existing automated tests
• New functions include new tests
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged
• Visually tested in supported browsers and devices
• Project documentation has been updated (including the "Unreleased" section of the CHANGELOG)

[coveralls]

Coverage decreased (-0.04%) to 99.959% when pulling a488c58 on fix-feedback into 277ef0f on master.

[coveralls]

Coverage remained the same at 100.0% when pulling e36e5a1 on fix-feedback into 277ef0f on master.

[schbetsy]

With this change, I was able to submit feedback through the form, and I saw that the query string (including program information) was saved in the url field of the feedback. LGTM.