MYLOC-105 Adding BBCCookies module.

Adding a module to encapsulate interaction with window.bbccookies.

I expect the UI layer to use isPersonalisationDisabled() as follows:
```
bbcCookies = new BBCCookies();
if (false === bbcCookies.isPersonalisationDisabled()) {
  // do something with cookies and local storage
}
```

If window.bbccookies is not available isPersonalisationDisabled() will return false so we can use cookies etc.

If the method was isPersonalisationEnabled() then it would return false if window.bbccookies is unavailable and we do not want this to happen eg running UI components in a non-BBC page.

this file needs to be added to test/index.html