[NPANDAY-480] add silverlight exclusion here too

System scope seems to drag runtime dependencies in some cases, overlapping
with the previous definition and causing Silverlight client applications
to appear in the wrong directory

git-svn-id: https://svn.apache.org/repos/asf/incubator/npanday/trunk@1572383 13f79535-47bb-0310-9956-ffa450edef68