RFR 8167459: Add debug output for indicating if a chosen ciphersuite was legacy.

[Bradford Wetmore]

Hi Xuelei,

We should provide more information about which ciphersuites were 
actually considered for a handshake and why they were ultimately 
chosen/not chosen, but for now we have been requested to add a debug 
message to indicate whether or not the selected ciphersuite was legacy.

Examples:

% java -Djavax.net.debug=all MyClass // or % java -Djavax.net.debug=ssl 
MyClass
     ...deleted...
     Standard ciphersuite chosen: TLS_RSA_WITH_AES_128_CBC_SHA
     ...deleted...

or

     ...deleted...
     Legacy ciphersuite chosen: SSL_RSA_WITH_RC4_128_SHA
     ...deleted...

The proposed simple change is:

     https://bugs.openjdk.java.net/browse/JDK-8167459
     http://cr.openjdk.java.net/~wetmore/8167459/webrev.00/

Thanks,

Brad