Fixed issues

Review the list of Flink and SQL Stream Builder issues that are resolved in Cloudera Streaming Analytics 1.6.0.

CSA-2389: Describing Kafka table fails when array is nested in schema
The issue about describing a Kafka table when an arrays is nested within the schema is fixed.
CSA-2321: SASL/PLAINTEXT is not available
The issue regarding the SASL/PLAINTEXT protocol not being available when using Kafka as a data provider for SQL Stream Builder is fixed.
CSA-2301: Transformation error when Kafka has null values
The issue regarding the transformation error when there are null values in Kafka messages is fixed.
CSA-1985: DROP TABLE limitation when using Webhook table
The issue regarding the execution of DROP TABLE statement when using Webhook table is fixed.