Diffs consumption re boundaries

[gregallensworth]

Expanding on the work done in #13 in regards to boundaries...

We've been following the openmaptiles method, in which boundaries are loaded. This is less than optimally, as it takes a half-hour to tun and is "just a second thing" Ideally, we would modify the mapping.yaml so that the boundaries were imported via imposm3 like everything else.

See what we can do about this. Ideal targets would include:

• [ ] remove the ohmborders tasks and documentation, as they would not be used anymore

• [ ] adjust the mapping.yaml to import boundaries. refer to the ohmborder source code to find the filtering and features

• [ ] purge the DB and reload, confirm presence of boundaries

• [ ] make some boundary-related change to OHM data, watch it propagate into vector tiles in our usual timeframe

[danrademacher]

Shifting temporarily to @jeffreyameyer so he can include thoughts and sketch on a broader solution to the low zoom border problem.

[danrademacher]

I[;m going to close this out and make a new issue based on latest approach