[8u] RFR for backport JDK-8226374: Restrict TLS signature schemes and named groups

[Alexey Bakhtin]

Hi,

I’d like to request a review for the 8u backport of JDK-8226374.

Original bug:
https://bugs.openjdk.java.net/browse/JDK-8226374
https://hg.openjdk.java.net/jdk/jdk/rev/a93b7b28f644

Original patch can not apply cleanly, because of difference in TLS implementation.

8u webrev:
http://cr.openjdk.java.net/~bae/8226374/webrev.00/

Thank you.
Alexey