title: D3.js, trouble initiating shp2json - encoding-indexes error
body: <p>I'm trying to follow the tutorial Mike Bostock did for <a href="https://medium.com/@mbostock/command-line-cartography-part-1-897aa8f8ca2c#.wkwy54o6n" rel="nofollow noreferrer">Command Line Cartography</a> (which is a great help). Right after installing <a href="https://www.npmjs.com/package/shapefile" rel="nofollow noreferrer">shapefile</a> and running the shp2json step [shp2json cb_2014_06_tract_500k.shp -o ca.json] I get this error message:
  “error: Decoder not present. Did you forget to include encoding-indexes.js first?” an error message which originates from the <a href="https://www.npmjs.com/package/text-encoding" rel="nofollow noreferrer">text-encoding</a> package from NPM.   </p>
  
  <p>In trying to diagnoise the problem, I figured I should manually install text-encoding as it's in the shp2json dependency list but, didn't appear to be loading. I also reinstalled node to downgrade from 7.3.0 to 6.9.2 and a number of other things (my hacking around looking for a solution for a few hours) but, am stuck. Is this just a matter of updating a package.json?   </p>
  
  <p>I’m using Windows7, the env variables is set I believe correctly to \Users\myAccount\AppData\Roaming\npm. I’ve installed all packages globally as well. Thanks for any insight.</p>