BigQuery

#### Docs: https://stephenplusplus.github.io/gcloud-node/#/docs/master/bigquery

##### Todo List (current):

- [x] Unit tests
- [x] Regression tests
- [ ] Update use cases from the doc examples to less kitten-based use cases :smirk_cat: 
This is sort of a nit. If it's undeclared, it will throw an Exception. Also, in < ES5 (doesn't really pertain here) you could redefine undefined.

``` js
assert.strictEqual(x, undefined); // ReferenceError: x is not defined
assert.strictEqual(typeof x, 'undefined'); // No error, this works as expected.
```

[Related stack overflow article](http://stackoverflow.com/questions/4725603/variable-undefined-vs-typeof-variable-undefined)