Add release notes for supporting CMEK for BigQuery connector ([]
Add release notes for supporting CMEK for BigQuery connector ([]

	Change on 2018/05/22 by dagang <dagang@google.com>

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=197589490

GoogleCloudDataproc/hadoop-connectors,GoogleCloudDataproc/hadoop-connectors