OAK-1850 - Dump help details for various command supported by oak-run

Added support for help option to various commands. This required updating the jopt-simple to 4.6 version

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1596759 13f79535-47bb-0310-9956-ffa450edef68
OAK-1850 - Dump help details for various command supported by oak-run

Updating ScalabilityRunner also

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1596760 13f79535-47bb-0310-9956-ffa450edef68