Review Request: JDK-8181033: Confusing message: A JNI error has occurred, please check your installation and try again

[Mandy Chung]

http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8181033/webrev.00/

This fixes the launcher to print the exception being thrown rather than
the confusing message "Error: A JNI error has occurred, please check
your installation and try again”.  A few attempts to improve this to 
catch ClassNotFoundException and LinkageError.  This catches other cases.

Mandy