Use pangify to convert your poly and coor files into a friendly javascript format.
npm install -g pangify
pangify {OPTIONS} [MODEL ...]
MODEL is the path and name of a file. Omit the extension and see option -i.
OPTIONS are:
-i Comma seperated input extensions. Default is -i poly,coor
-d Set ouput directory. Default is the path to file.
-v Show tokenized ouput. For debugging.
Here is one way to get a set of poly and coor files
wget -A poly,coor -m -nd https://users.soe.ucsc.edu/~pang/160/s15/data/