[NPANDAY-609] add generated sources for XAML

Note that any includeSources listed for obj are now ignored, and that
these are picked up automatically, in contrast to previous behaviour.

git-svn-id: https://svn.apache.org/repos/asf/incubator/npanday/trunk@1572435 13f79535-47bb-0310-9956-ffa450edef68