After extracting data via bqr_extract_data download the extract from the Google Storage bucket.
If more than 1GB, will save multiple .csv files with prefix "N_" to filename.
bqr_download_extract(extractJob, filename = NULL)An extract job from bqr_extract_data
Where to save the csv file. If NULL then uses objectname.
TRUE if successfully downloaded
Other BigQuery asynch query functions: bqr_extract_data,
bqr_get_job,
bqr_grant_extract_access,
bqr_query_asynch,
bqr_wait_for_job