RFR (JAXP): 8146606: Catalog.matchSystem() appends an extra '/' to the matched result

[huizhe wang]

Please review a fix to the match method of RewriteSystem and RewriteUri 
that resulted in an extra slash in the URI.

Webrev:
     http://cr.openjdk.java.net/~joehw/jdk9/8146606/webrev/
Issue:
     https://bugs.openjdk.java.net/browse/JDK-8146606

Thanks,
Joe