Reorganize SSL test structures

Move custom server and client options from the test dictionary to an
"extra" section of each server/client. Rename test expectations to say
"Expected".

This is a big but straightforward change. Primarily, this allows us to
specify multiple server and client contexts without redefining the
custom options for each of them. For example, instead of
"ServerNPNProtocols", "Server2NPNProtocols", "ResumeServerNPNProtocols",
we now have, "NPNProtocols".

This simplifies writing resumption and SNI tests. The first application
will be resumption tests for NPN and ALPN.

Regrouping the options also makes it clearer which options apply to the
server, which apply to the client, which configure the test, and which
are test expectations.

Reviewed-by: Richard Levitte <levitte@openssl.org>