support reference on other impl type than impl.widget

https://issues.apache.org/jira/browse/ 2001-01-01 deliveredby note support reference on other impl type than impl.widget LR 2001-01-01 TUSCANY-2850 in progress repository_vid note Enhance artfact processing performance by returning URI and location URL in one call LR 2001-01-01 TUSCANY-3395 in progress repository_vid note Add support for identifying the SCA Spec Version for contribution metadata LR 2001-01-01 TUSCANY-3397 in progress repository_vid note