OAK-1133: Observation listener PLUS
Rename FilterProvider to JcrFilterProvider

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1545602 13f79535-47bb-0310-9956-ffa450edef68
OAK-1133: Observation listener PLUS
Extract FilterProvider interface to prepare injection of custom filters (WIP)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1545603 13f79535-47bb-0310-9956-ffa450edef68