@trivial: lower logging level for registering of observation listener, reduce noise in unit-test.log

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1567169 13f79535-47bb-0310-9956-ffa450edef68
OAK-1413: Add scalability tests for large operations
Initial tests for asserting scalability of large commits, copy of large trees, move of large trees, many siblings, many pending observation events. All currently @Ignored

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1567170 13f79535-47bb-0310-9956-ffa450edef68