#935 - Added convenience contractor for open admin property.
#935 - A "SectionCrumb" in open admin has a sectionIdentifier that is translated into a class.    Generally this is a one to one concern but in some cases, we may want multiple sectionIdentifiers to utilize the same underlying class.    A good example might be to separate admin menus for Carts and Orders which both use the same underlying entity.     Allowing an "originalSectionIdentifier" provides a quick hack to support this.    A better solution might be to use the term sectionClass instead of sectionIdentifier for the most common usage scenarios.