Add basic map with covid vaccination sites

[MoralCode]

data from esri ArcGIS thingy here: https://covid-19-giscorps.hub.arcgis.com/datasets/covid19-vaccination-locations-in-the-united-states?geometry=-16.621%2C-87.862%2C1.660%2C88.858&showData=true

uses leafletjs for the map

tutorial for esri and leaflet stuff here: https://esri.github.io/esri-leaflet/tutorials/create-your-first-app.html

Things to do:

• style points by status of the vaccination sire, like https://giscorps.maps.arcgis.com/home/webmap/viewer.html?useExisting=1&layers=c50a1a352e944a66aed98e61952051ef does
• figure out how to allow people to click on the map and see info on that vaccination site (maybe in a new tab?)
• maybe find a better basemap like topographic or some plain light gray thing like the other maps use? this should be a one line change