Renamed the class org.ofbiz.entity.transaction.TransactionFactory into org.ofbiz.entity.transaction.TransactionFactoryLoader: this name better describe its purpose.

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/branches/framework-api-cleanup@1619871 13f79535-47bb-0310-9956-ffa450edef68