Forgot to do that when I replaced the cert in #4096. Thanks asan for
catching that!

(via ahh@google.com)
Under some configurations gRPC includes google3 base headers.  google3
has a namespace "thread" which mixes poorly with unqualified use of the
type std::thread; adding that namespace to various google3 headers
breaks this test.

The encoding of the issuer field in this cert is now a PRINTABLESTRING
as opposed to UTF8STRING in the previous server1.pem which was causing
the Go issue.

Fixes #4086.

Make payloads respect the new defaults

Enable reasonable default if resp size not specified

Have not yet added tests with security support, coming soon

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

of the proto if desired, or just goes to pick_unused_port_or_die if not
specified

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

issue addressed by commit: e6cd0e70, the right way)

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

The composite channel credentials creation does not change the passed-in
channel creds anymore.