Added several methods to the BigQuery client for managing datasets and generating schema

get_datasets()
get_dataset(dataset)
create_dataset(dataset,friendly_name=None,description=None,access=None)
delete_dataset(dataset)
update_dataset(dataset,friendly_name=None,description=None,access=None)
client.patch_dataset(dataset,friendly_name=None,description=None,access=None)

And a helper fn that calculates a schema given a record:
client.schema_from_record(record)