An ATK object which encapsulates a link or set of links (for instance in the case of client-side image maps) in a hypertext document.
It may implement the AtkAction interface. AtkHyperlink may also be used to refer to inline embedded content, since it allows specification of
a start and end offset within the host AtkHypertext object.
Since the document that a link is associated with may have changed this
method returns true if the link is still valid (with respect to the document it references) and false otherwise.