fix: link all outstanding TODO items to a ticket

[bacongobbler]

closes #800

Note: as pointed out in #800, report_todo and report_fixme are only available on the nightly channel. If you're on the stable channel, you will see a ton of error messages any time you run cargo fmt. Perhaps these should be commented out? Let me know how you'd like to proceed here.

><> rustup default stable
info: using existing install for 'stable-x86_64-apple-darwin'
info: default toolchain set to 'stable-x86_64-apple-darwin'

  stable-x86_64-apple-darwin unchanged - rustc 1.41.0 (5e1a79984 2020-01-27)

><> cargo fmt
Warning: can't set `report_todo = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_fixme = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_todo = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_fixme = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_todo = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_fixme = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_todo = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_fixme = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_todo = Unnumbered`, unstable features are only available in nightly channel.
Warning: can't set `report_fixme = Unnumbered`, unstable features are only available in nightly channel.

Signed-off-by: Matthew Fisher matt.fisher@microsoft.com

[jstarry]

I'm fine with the warnings, thanks so much for doing this!