Feature-allow-local-EHDP-data

[cgettings]

The namesake feature is mostly for my benefit, because I have IIS running on my laptop and I work on the train a lot.

There's also some other stuff in here w/ dependencies.

FYI @mmontesanonyc

PR checklist:

• [x] Changes previewed and QC'ed
• [x] In PR, mention team member for FYI, review, or approval

[mmontesanonyc]

@cgettings do you observe any CSS conflicts having nyc core framework in assets but also importing bootstrap and popper through npm?

[mmontesanonyc]

@cgettings Nope, didn't observe any, just wanted to doublecheck you're on the lookout.