"Unit tests" demo is not working

[The "Unit tests" demo](https://nf404.github.io/crypto-api/example/unit-tests.html) is not working due to 404 error.

A referred file

```
https://cdn.rawgit.com/mochajs/mocha/5.2.0/mocha.js
```

is redirected to

```
https://cdn.jsdelivr.net/gh/mochajs/mocha@5.2.0/mocha.js
```

and 404 error is returned for this URL.