[9] request for review: 8055207: keystore and truststore debug output could be much better

[Vincent Ryan]

Please review this trivial enhancement to JSSE to warn when TLS client authentication cannot be completed
because of difficulty locating a suitable client certificate. (Keystore file paths are already displayed by JSSE, when known)

This is useful to help troubleshoot configuration issues related to keystores and truststores.
Thanks.


Webrev: http://cr.openjdk.java.net/~vinnie/8055207/webrev.00/
Bug: https://bugs.openjdk.java.net/browse/JDK-8055207