drill

5dbaafbe - DRILL-3623: For limit 0 queries, optionally use a shorter execution path when result column types are known

DRILL-3623: For limit 0 queries, optionally use a shorter execution path when result column types are known + "planner.enable_limit0_optimization" option is disabled by default + Print plan in PlanTestBase if TEST_QUERY_PRINTING_SILENT is set + Fix DrillTestWrapper to verify expected and actual schema + Correct the schema of results in TestInbuiltHiveUDFs#testXpath_Double This closes #405