OAK-2105: Review padding for blobs collection

Add function to get stats about blobs collection

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1625898 13f79535-47bb-0310-9956-ffa450edef68
OAK-2050 Query engine: disable or restrict built-in full-text engine

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1625902 13f79535-47bb-0310-9956-ffa450edef68