Base class for content class element types.
For every attribute/property that can be compared and/or saved there has to be an IRDAttribute created and registered, so that the comparison/assignement can be made independent of the element type.
Inheritance: LanguageDependentPartialRedDotProjectObject, IContentClassElement
 internal TargetContainerPreassignment(ContentClassElement element)
 {
     _element = element;
 }
 internal TargetContainerPreassignment(ContentClassElement element)
 {
     _element = element;
 }