RFR 8176536: Backport weak algorithms checking

[Anthony Scarpino]

Hi,

I need a review of this large backport of the weak algorithm checking 
code to jdk8.

In mosts cases the changes are either identical or 95% of what is in 
jdk9, the below two files deviate the most from jdk9 because of other 
jdk9 features:
   src/share/classes/sun/security/ssl/SSLContextImpl.java
   src/share/classes/sun/security/validator/PKIXValidator.java

http://cr.openjdk.java.net/~ascarpino/8176536/webrev/

thanks

Tony