Simple Benchmark

Requires `npm install`.

Then run `grunt bench`

From my initial results, it's not looking too good:

```
Running suite Simple [benchmarks/simple/simple.bench.js]...
>> NoPongular x 726,754 ops/sec ±1.87% (83 runs sampled)
>> WithPongular x 5,098 ops/sec ±2.33% (86 runs sampled)
Fastest test is NoPongular at 142.6x faster than WithPongular
```

@FungusHumungus let me know if you think the test I wrote is a fair comparison or not? I'd still like to perform a more "complex" benchmark that would span across multiple files. I believe that would probably be more fair and closer to a more practical use case. But for now, thought I'd show you what I got done so far with this pull request.

One other change included in this pull request is the addition of the "files" `package.json` param. This means when people are installing the package through `npm` it will only include the files necessary to use the `pongular` library (and the examples for quick reference if needed) and exclude downloading unnecessary files like the `benchmarks`.