OAK-1969: Duplicate observation events when using JackrabbitEventFilter
Deduplicate list of paths passed in JackrabbitEventFilter

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1610658 13f79535-47bb-0310-9956-ffa450edef68
OAK-1966 - Add Hint for selecting more performant index in MongoDocumentStore#query

_modified index would be used if the delta between now and time being queried for is less than 120 secs (configurable via oak.mongo.maxDeltaForModTimeIdxSecs)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1610664 13f79535-47bb-0310-9956-ffa450edef68