Add map feature

[awoods]

This feature adds a new option/page in the navbar that displays all items in the collection that have a value in the latitude and longitude columns in the project CSV file. This works out-of-the-box.

This is a port from https://github.com/CollectionBuilder/collectionbuilder-csv.

Related user documentation pull-request: minicomp/wiki#34

For an existing demonstration: https://history.lakecountypubliclibrary.org/cmhc/map/

[bmschmidt]

I'll leave it to @mnyrop and others how this fits into Wax, but a small note on https://github.com/minicomp/wax/pull/149/files#diff-5a448a10ed6933c46c8043cb497427b7536d7d2b103cc32fafecd5d1a0ecbfb1R49-R53: if you want to put in preset layers into a wax site, I would recommend having multiple different corporate sources, not just ESRI--include also some tiles from stamen, OSM, etc.

In an absolutist sense there really ought to be some way to cache tiles locally as with https://openmaptiles.org/. But even failing that, better not to have reliance on just ESRI sets.

[awoods]

Thanks, @bmschmidt . It is a good point and a good suggestion to show the pattern for including other map layer sources. I also agree that there is an open question regarding whether this mapping functionality belongs in the scope and goals of Wax. Before working through the details of the former, I will wait on a signal about the latter.