A patch from Christian Carlow for "Production Run Content button throws unable to resolve class GenericValue error" https://issues.apache.org/jira/browse/OFBIZ-5923

The GenericValue class needs to be imported for resolution.

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1647338 13f79535-47bb-0310-9956-ffa450edef68