Generate a return with the value s

Property definitions

nitc $ AbstractCompilerVisitor :: ret
	# Generate a return with the value `s`
	fun ret(s: RuntimeVariable)
	do
		self.assign(self.frame.returnvar.as(not null), s)
		self.add("goto {self.frame.returnlabel.as(not null)};")
	end
src/compiler/abstract_compiler.nit:1968,2--1973,4