Adds a test for greenplum's db-create-table-like
Adds a test for greenplum's db-create-table-like

that checks whether it preserves DISTRIBUTED BY columns

HazyResearch/deepdive,HazyResearch/deepdive,HazyResearch/deepdive,HazyResearch/deepdive,sky-xu/deepdive,shahin/deepdive,shahin/deepdive,sky-xu/deepdive