OAK-301: Document Oak
typos

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1507243 13f79535-47bb-0310-9956-ffa450edef68
OAK-301: Document Oak
refine todos

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1507244 13f79535-47bb-0310-9956-ffa450edef68