def before_destroy_rebuild_node_map
				# All the node_maps from this node
				self.survey.node_maps.select { |i|
					i.node == self
				}.each { |node_map|
					# Remap all of this nodes children to the parent
					node_map.children.each  { |child|
						node_map.parent.children << child
					}
				}

				true
			end
def before_destroy_rebuild_node_map
				# All the node_maps from this node
				self.survey.node_maps.select { |i|
					i.node == self
				}.each { |node_map|
					# Remap all of this nodes children to the parent
					node_map.children.each  { |child|
						node_map.parent.children << child
					}
				}

				true
			end
Before a node is destroyed, will re-build the node_map links from parent to child if they exist