Started migration to Play 2.3.1 for custom SSL Engine support.

A single test is still failing - had be modified to compile.
Added custom SSL engine to enable client authentication

Added custom SSL engine to enable client authentication.  The
nsi-requester can now be deployed without a reverse proxy front end.
Also added example scripts for both a standalone HTTPS server, and when
being fronted by a Apache httpd.
Merge pull request #1 from BandwidthOnDemand/Update-to-Play-framework-2.3.1

Update to play framework 2.3.1