Spark 2.4.2 and Delta Lake

[ploddi]

Databricks open-sources Delta Lake recently. According to docs (https://docs.delta.io/latest/quick-start.html#set-up-apache-spark-with-delta) it requires Spark 2.4.2 or above.

Can you please release quick update to 2.4.2.

[vishnu2kmohan]

@ploddi Ack and thanks for the suggestions, we'll take this into consideration for our next update.

cc @samvantran @akirillov