RFR: 8165944 jar utility doesn't process more than one -C argument

[Steve Drach]

Hi,

Please review these changes to the jar tool to fix a capability regression I introduced in an earlier revision.  The issue is that this

$ jar -cf test.jar -C test1 . -C test2 .

only puts the files under test1 in the jar and ignores the files under test2.  The DoubleCs test verified the problem and the solution.

issue: https://bugs.openjdk.java.net/browse/JDK-8165944 <https://bugs.openjdk.java.net/browse/JDK-8165944>
webrev: http://cr.openjdk.java.net/~sdrach/8165944/webrev.00/ <http://cr.openjdk.java.net/~sdrach/8165944/webrev.00/>

Thanks,
Steve