OAK-1360: Rename o.a.j.o.plugins.mongomk to o.a.j.o.plugins.document
- move MongoBlob* to document.mongo package
- clean up occurrences of MongoDB in JavaDoc

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1562055 13f79535-47bb-0310-9956-ffa450edef68