fix dead link to webapps/test.xml

test-webapps/test-jetty-webapp/src/main/config/webapps/test.xml moved to test-webapps/test-jetty-webapp/src/main/config/demo-base/webapps/test.xml
Merge pull request #31 from yusuke/test-xml-deadlink

fix dead link to webapps/test.xml