Export an actually working es6 module

[kapouer]

Fix #3

[kapouer]

This assumes npm run preversion is run from a reasonably bash-compatible shell...

[miraclx]

lgtm; Thanks for this.

[miraclx]

Does the readme need an update? https://github.com/miraclx/xbytes#usage

[kapouer]

I don't think so - i made it so it doesn't change anything w.r.t. usage.

[miraclx]

Great. All good then.

[kapouer]

FYI you can do a test with a test.mjs file (provided node_modules/xbytes is present)

import xbytes from "xbytes"
console.log(xbytes(100000));

then

$ node test.js
(node:710173) ExperimentalWarning: The ESM module loader is experimental.
100.00 KB

(that's with node 12).