Add domain root directory to Weblogic classpath

WebLogic automatically includes the domain root folder (i.e. weblogic/home/user_projects/domains/mydomain) in the classpath when starting using the startWeblogic scripts. This folder should be added to the classpath that Cargo uses to start an existing domain, as it is a common place to include configuration files, property files, log4j configurations, etc. These could all be managed via the extraClasspath (or dependencies in Maven2) but it is much simpler and more straightforward just to include that folder in the classpath. The attached fix adds one line at line 141 to add the path element.