[Map] adding and handling font glyphs

[rudokemper]

The tileserver generating the map requires font glyphs (in pbf) to be added to this directory:
https://github.com/rubyforgood/terrastories/tree/master/tileserver/data/fonts/

The PBF JavaScript library for decoding and encoding protocol buffers is available here: https://github.com/mapbox/pbf

Currently, we only have Open Sans Regular available in our /fonts/ directory. We should make more fonts available.

Option 1: generate and add pbf's for all other versions of Open Sans and other fonts found here: https://github.com/openmaptiles/fonts/tree/master/open-sans

Option 2: installing and using Fontnik https://github.com/mapbox/fontnik

Or is there a better solution?