Create Unit Tests for JndiSessionRegistrarBase.unbindEjb()

We need a test to:

• Deploy an EJB (there are already a couple sample ones available in src/test/java)
• Test that all expected bindings are there (very similar to what is done "proxy session" tests)
• Undeploy the EJB
• Test that all the previous bindings are no longer available (ie. NameNotFoundException on lookup)