The `loop` keyword

Property definitions

	# The `loop` keyword
	var n_kwloop: TKwloop is writable, noinit

src/parser/parser_nodes.nit:2026,2--2027,42

	redef fun n_kwloop=(node)
	do
		_n_kwloop = node
		node.parent = self
	end

src/parser/parser_prod.nit:3318,2--3322,4