[examples] Missing archive tag from Fluent Job examples

When -runjar option is used to execute a fluentjob example, oozie sets the app path to a newly created (timestamped) directory and copies the freshly generated workflow.xml file to this directory:

/user/username/oozie-fluent-job-api-generated/gen_app_1536586664643

This directory does not contain any other jar file, hence some of the examples are not working. 

For instance the JavaMain example cannot find the DemoJavaMain class:

180910095203189-oozie-andr-W] ACTION[0000020-180910095203189-oozie-andr-W@java-main] Launcher exception: java.lang.ClassNotFoundException: Class org.apache.oozie.example.DemoJavaMain not found
java.lang.RuntimeException: java.lang.ClassNotFoundException: Class org.apache.oozie.example.DemoJavaMain not found

 
The examples should be modified to allow the user to specify the path of an archive which contains the necessary files.