Use VarHandle interface. Part I.

[sergeykhegay]

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[yanxinyi]

used setCacheBlocks to disable the block cache.  https://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html#setCacheBlocks-boolean- Current implementation deprecated the PhoenixRDD.scala file, so I modified PhoenixDataSource.java with an additional option.