OPENDJ-917 (CR-1731) HTTP Connection Handler - Fix HTTPS support



HTTPS was wrongly configured: code was configuring an SSLEngine that was then never used.
Changed the code to configure an SSLEngineConfigurator that is passed down to Grizzly HTTP server.



(Un)surprisingly I hit a bug on my Linux Mint:
https://bugs.launchpad.net/ubuntu/+source/openjdk-6/+bug/1006776
I had to modify /etc/java-6-openjdk/security/java.security so it uses the sun Elliptic Curve implementation by changing the line
    security.provider.9=sun.security.pkcs11.SunPKCS11 ${java.home}/lib/security/nss.cfg
to
    security.provider.9=sun.security.ec.SunEC
    #security.provider.10=sun.security.pkcs11.SunPKCS11 ${java.home}/lib/security/nss.cfg



HTTPConnectionHandler.java:
Replaced instance members sslContext and sslEngine with sslEngineConfigurator.
Renamed createSSLEngine() into createSSLEngineConfigurator().
In createSSLContext(), removed the try / catch block duplicated with the one in createSSLEngineConfigurator().
As a consequence, the following methods changed: configureSSL(), getEnabledSSLCipherSuites(), getEnabledSSLProtocols(), getSSLEngine(), isConfigurationAcceptable(), startHttpServer().