Add fallback querry to jconsole plugin

JConsolePlugin connecects to default port, despite chance to use proper info.
Problem:
Unless I miss somethingm JConsole has a bit tight isolation between components. There is no way for AS7 JConsolePlugin to access "connect dialog" info. Hence it has no idea what is the content of URL being passed as remote.

AS7 JConsolePlugin checks if MBeanServerConnection is instance of RemotinConnection. If its not, it fallbacks to default: localhost:9990.
However we can check for socket bindings and try to connect to proper socket.