Exchange_rule: run simple query 's generated physical plan through QS. Reverse change to Foreman.
Write the physical plan into log for debug purpose.
Exchange_rule : SortPrel, SingleMergeExchangePrel, HashToRandomPrel - get physical operators.
More WIP for HashToRandomExchange, SingleMergeExchange, StreamAgg.
Use optiq 0.6-SNAPSHOT.  Planner is provided with a list of RelTraitDefs to register.
Minor code change due to Optiq 0.6-SNAPSHOT change.

Rename ConnectionConfig to DrillConnectionConfig due to optiq-0.6-SNAPSHOT add an interface with same name.
Cherry-pick recent changes from optiq_opt2 branch.
DRILL-396: QuerySubmitter enhancements
DRILL-413 Parse issue in QuerySubmitter