Recursively draw children of mentity

Property definitions

nitc $ InheritanceGraph :: draw_children
	# Recursively draw children of mentity
	fun draw_children(mentity: MEntity, max_depth: nullable Int, current_depth: nullable Int) do
		if done_children.has(mentity) then return
		done_children.add mentity
		current_depth = current_depth or else 0
		if max_depth != null and current_depth >= max_depth then
			to_dotdotdot(mentity)
			return
		end
		var children = mentity.collect_children(mainmodule, filter)
		if children.length > 10 then
			to_dotdotdot(mentity)
			return
		end
		for child in children do
			if child isa MGroup then
				if child.mpackage.mgroups.first == child then child = child.mpackage
			end
			draw_edge(child, mentity)
		end
		for child in children do
			if child isa MGroup then
				if child.mpackage.mgroups.first == child then child = child.mpackage
			end
			draw_children(child, max_depth, current_depth + 1)
		end
	end
src/doc/commands/commands_graph.nit:261,2--287,4