RFR 8055747: Move SimpleSSLContext to jdk/testlibrary

[Michael McMahon]

Before I push the other change to HttpsURLConnection, I'd like
to make this change to stop the proliferation of binary testkeys files
in the test tree and make the SimpleSSLContext class more accessible.

http://cr.openjdk.java.net/~michaelm/8055747/webrev.01/

Thanks,
Michael