[9] request for review: 8049171: Additional tests for jarsigner's warnings

[Artem Smotrakov]

Hello,

Please review a couple of new tests for jarsigner's warnings. Basically 
tests run jarsigner and check warning/error messages and exit codes 
according to [1].

https://bugs.openjdk.java.net/browse/JDK-8049171
http://cr.openjdk.java.net/~asmotrak/8049171/webrev.00

[1] 
http://docs.oracle.com/javase/7/docs/technotes/tools/windows/jarsigner.html

Artem