Convert encodings, uses iconv by default and fallbacks to iconv-lite if needed

 encoding is a simple wrapper around
 node-iconv (https://github.com/bnoordhuis/node-iconv) and
 iconv-lite (https://github.com/ashtuchkin/iconv-lite/) to convert strings
 from one encoding to another. If node-iconv is not available for some reason,
 iconv-lite will be used instead of it as a fallback.
 .
 Node.js is an event-based server-side JavaScript engine.