DERBY-3195; Describe if default security manager & policy is installed or not on each of the mechanisms to start the network server.
   updating the javadoc for NetworkServerControl to reflect information about the security manager.


git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1646373 13f79535-47bb-0310-9956-ffa450edef68