fix for issue #1217
Privilege checks are done in the JmxClientConnection code. Due to
JMX design choice (See chapter 13.4.3,page 210 of the JMX Specification,
version 1.4 Final Release - http://jcp.org/en/jsr/detail?id=160)
JMX_NOTIFY privilege cannot be checked when a remote client adds a
Listener. For this reason, we have chosen to allow JMX
connection only if the user has the JMX_READ privilege (at least).
The JMX_READ privilege is now also check during connection establishment.

Some clean up is also added in PrivilegeTestCase.java