RFR: RT-33792: Implement specular lighting as specified for the PhongMaterial

[Vadim Pakhnushev]

Chien, Kevin,
Please review the fix here:
https://javafx-jira.kenai.com/browse/RT-33792
http://cr.openjdk.java.net/~vadim/RT-33792/webrev.00/

Thanks,
Vadim