feat: add broccoli 2 compatible plugin implementation
feat: add broccoli 2 compatible plugin implementation

BREAKING CHANGE:
- Port is still configurable, but now has to supplied using a nested livereload
 object
- Configure the target (html) files using the required target property and a
JavaScript Regular Expression

```js
const BroccoliInjectLivereload = require('broccoli-inject-livereload')

const reloadable = new BroccoliInjectLivereload('app', {
    target: 'index.html',
    livereload: {
        port: 12345
       }
    })

module.exports = reloadable
```

Dremora/broccoli-inject-livereload