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: 
If it's there just for show, I'd just say use a noop because callback functionality is tested in another unit test.