I also added some unrequested const's

Revive it in tests as well

- make the directory structure match the package structure
- sanitize the package structure (test --> testing)
- add auto-detection of proto file dependencies

Remove some unused options and make server_threads relevant
Start stubbing out better qps/core calculations

reset option to the mark, create a closed loop config params (empty
message) for consistency with other tests.

one for control.
Eliminate the use of our own SimpleRequest and SimpleResponse and
instead share the one from end2end testing

This change contains a lot of ugly changes, such as changing
std::vector to allocation by new, etc.