* add flag to handler
* cleanup
* concurrency control
* add flag for handler setters
* update service flags
* fix event handlers
* more handlers
* make sure behavior is unchanged if flag is off
* cleanup
* add test case for parallel processing
* comments
* stop dispatcher in test
* add log for request lifespan
* cleanup and add comments
* correctly release semaphore
* remove deleted file from merge
* use await for semaphore release
* move handler invocation to await and adjust test
* cleanup exception handling and wrapper
* space
* loose assertion condition to make test stable
* Adds new graph comparison request handler to the Execution Plan Service.
* Code review changes
* Renames execution plan compare params, result, and request classes.
* Renames ShowPlan directories along with corresponding namespaces
* Renames ShowPlanGraphUtils to ExecutionPlanGraphUtils
* Revert "Renames ShowPlanGraphUtils to ExecutionPlanGraphUtils"
This reverts commit 5dc2696ae906598447eed7360a3f342218432b83.
* Reverts show plan tests name change.
* Renames show plan test XML files.
* Renames ported directory to ShowPlan and updates namespace accordingly
