CASC-231 HttpsURLConnectonFactory is Not Serializable

Problem: THe HttpsURLConnectionFactory is not serializable, causing problems for clients that must serialize
the principal (which depends on a ProxyRetriever).

Solution: Make the HttpsURLConnectionFactory serializable.

QA Notes: added unit test to confirm serialize-deserialize
I asked that of someone else once (it was either Marvin or Misagh, I forgot who) and basically as long as you change it each time you make a change its fine.  So starting with 1 is okay.