Part of the visitor pattern implementation for markup data. This method is overridden in each leaf implementation. The implementation should call the Visit... method on the visitor corresponding to their object type, passing themselves (i.e. this) as the parameter. Objects that contain other objects (e.g. implementations of ISegment or IOtherMarker) should NOT apply the visitor to their content items. It must be left to the visitor implementation to 'decide' whether the visitor 'wants' to visit the sub-items of a node.

Removes this node from its parent container (if any).