(TK-96) Fixes for default SSL protocols

This commit changes our default SSL protocols to include only
TLSv1, TLSv1.1, and TLSv1.2.  It also ensures that the server
is initialized with these protocols if the user doesn't specify
their own list via configuration.

Lastly, it makes sure that we use that same list of default
protocols for `add-proxy-route`, in the case where the user
has specified an explicit list of pem files for SSL but has
not specified protocols.
(TK-96) Minor cleanup to SSLContextFactory initialization
(TK-96) Break proxy tests into more `deftest`s

Debugging can be really hard when there are too many `testing` blocks
inside a single `deftest`.  This commit just breaks the proxy
tests into more `deftest`s.