Convenience class to manage extensions/encapsulations. This class creates and manages object
extensions and encapsulations. An object, from here on denoted as 'original', can be encapsulated
in or extended by another object. An example would be the relation between an edge (original) and
an annotated edge. The annotated edge encapsulates/extends an edge, thereby augmenting it with
additional data. In symbolic form, if b is the original class, than a(b) would be its extension.
This concept is similar to java's extension where one class is derived from (extends) another