[RFC] - Add browser extension that fills data in FreeFileFillableForms

[zakpatterson]

@tmm1 has done some experimenting with building a browser extension targeting FFFF. We should build a renderer that sends final results to FFFF.

• At "Review and Print" step, user should have an option to "Send to FreeFileFillableForms"
  • If the browser extension is detected, the data should be sent to the browser extension
    • The extension should offer some summary view of the imported data, then offer a link and instructions to go to ffff.
    • Once at ffff, the extension should be able to add and fill all the necessary forms.
  • If the extension is not detected, provide a link to download the extension, and then complete the above