BigQuery: support Tables: patch #1564
Description
Add support for this:
https://cloud.google.com/bigquery/docs/reference/rest/v2/tables/patch
..unless it's already somehow possible to add or modify a field without specifying all the existing fields?
Internally BigQueryImpl.update seems to call bigQueryRpc.patch, but when I tried to call BigQuery.update with only one field (the field to be added), I got an error that the schema doesn't match with the existing one.