EntityConfig now implements the singleton pattern; thread safety is implemented with a static initialization.
Removed the EntityConfigUtil class whose main purpose was to guarantee that only one instance of EntityConfig would be initialized (no more required since now EntityConfig is a singleton); moved a couple of its static methods to the EntityConfig class.

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/branches/framework-api-cleanup@1619976 13f79535-47bb-0310-9956-ffa450edef68
Call the overloaded method instead of duplicating its content.

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/branches/framework-api-cleanup@1619977 13f79535-47bb-0310-9956-ffa450edef68