Add links to FB's warning. Add FAQ about common issues

BREAKING CHANGE: This changes the internal workings. A major release is
made to ensure minimal effect on downstream users.

Facebook has since release this software under the MIT license. This
commit does the same

BREAKING CHANGE: Change License to MIT from BSD+patents

Update warning to use the latest version from facebook/fbjs

closes #18

Since the problem with uglify is fixed there is not reason to keep
browser version which do not add any benefits. Actually it blocks us
from distributing `esm` version which is widely used these days and
supported by the most popular bundlers like webpack, rollup and parcel.

Here's a few links
facebook/fbjs#86 (comment)

Both uglify and babel minify support evaulation and eliminating

```js
(function () {
  function warning() {}

  var __DEV__ = 'production' !== 'production'

  if (__DEV__) {
    warning = function (msg) {
      console.log(msg)
    }
  }

  warning()
} ());
```

https://skalman.github.io/UglifyJS-online/

https://babeljs.io/repl#?babili=true&browsers=&build=&builtIns=false&code_lz=BQMwrgdgxgLglgewgAmASmQbwFDOeaeJZAdwEMAnCOCAc3SwF9tdkA3S5AfS4BEBRAGo9kAXmQByAA4UEAEzCxEECcgCEo8dNkKlSCSzxwQqHgOFcMOPHnJUatMfkh6UwALYBnWldY3kUEieCAA2AKYAdCEI9F4-fsjMeMysdtR06NiMqGhoANxAA&debug=false&forceAllTransforms=false&shippedProposals=false&circleciRepo=&evaluate=false&fileSize=false&lineWrap=false&presets=babili%2Cenv&prettier=false&targets=&version=6.26.0&envVersion=1.6.2

…version

Remove "browser" version

This section is no longer needed as browserify will evaluate boolean
vars and remove deadcode

Make use of standard release tools