UberJar will automatically create a Classworlds
configuration file for your application; however, you must
specify which class contains the main method for
your application. This is the class that will be invoked
when a user types: java -jar uber.jar.
Specifies that the plugin should not automatically create a
Classworlds configuration file because your application
already has its own. This property should be set to your
appropriate configuration. If this property is specified,
maven.uberjar.main is ignored.