Add Tone Targeting to Ad Calls

the same function as above? generalise it's name, so it can be used by both `contributors` and `tones`

Also, as commercial code needs to run on as wide a range of browsers, avoid using native array methods (they're patchy on old IEs); use lodash instead, e.g.

```
return map(tonalArray, function(tone) {
    ...
});
```