Fix for GRILL-538 - Map and SMB joins with parquet

Ran all unit tests with clientpositive/parquet* and clientnegative/parquet* which are listed below

-rw-r--r--  1 suma.shivaprasad  1492765578   978 May 29 17:02 parquet_create.q
-rw-r--r--  1 suma.shivaprasad  1492765578   937 May 29 17:02 parquet_ctas.q
-rw-r--r--  1 suma.shivaprasad  1492765578  2046 Aug  5 13:01 parquet_join.q
-rw-r--r--  1 suma.shivaprasad  1492765578  1088 May 29 17:02 parquet_partitioned.q
-rw-r--r--  1 suma.shivaprasad  1492765578   782 May 29 17:02 parquet_types.q'

-rw-r--r--  1 suma.shivaprasad  1492765578   94 May 29 17:02 parquet_char.q
-rw-r--r--  1 suma.shivaprasad  1492765578   90 May 29 17:02 parquet_date.q
-rw-r--r--  1 suma.shivaprasad  1492765578  104 May 29 17:02 parquet_decimal.q
-rw-r--r--  1 suma.shivaprasad  1492765578  105 May 29 17:02 parquet_timestamp.q
-rw-r--r--  1 suma.shivaprasad  1492765578  103 May 29 17:02 parquet_varchar.q