conf: add mjs/cjs exports

[ealush]

Q	A
Bug fix?	✖
New feature?	✔
Breaking change?	✖
Deprecations?	✖
Documentation?	✔
Tests added?	✔
Fixed issues	#298

require vs import

Depending on your node version and the module system you support you can use different syntax to include Vest.

Most compatible: commonjs

To be on the safe side and compatible with all node versions, use a require statement.

const vest = require('vest');
const { test, enforce } = vest;

Depending on your node version and used flag, your require statement might default to Vest's minified es5 bundle. If you want to make sure to use the non-minified es6 commonjs bundle, you can require it directly.

const vest = require('vest/vest.cjs.js');
const { test, enforce } = vest;

For supported environments: esm

If you want to explicitly load Vest's esm module, you can import it directly:

import vest, { test } from 'vest/esm/vest.mjs.js';

Node 14

With node 14's support of package entry points, node should be able to detect on its own which import style you use and load the correct bundle.

Both of the following should work:

import vest, { test } from 'vest';

const vest = require('vest');