OAK-28 Query implementation: code cleanup

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1481845 13f79535-47bb-0310-9956-ffa450edef68
OAK-318 Excerpt support

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1481846 13f79535-47bb-0310-9956-ffa450edef68