OAK-1046: Faster anonymous read operations

Move the getTestSession() call to outside the runTest() method to prevent the slow login() performance (OAK-634) from masking other performance issues.
Refactory the DeepTreeTests to reduce duplication of code.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1529176 13f79535-47bb-0310-9956-ffa450edef68
OAK-641: Improved benchmark tooling

Direct logs to stderr instead of stdout to simplify scripting.
Disable the annoying warnigns from JCR-3671.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1529177 13f79535-47bb-0310-9956-ffa450edef68