* src/Main.hs: Store zero as the fake static link of main.
	* src/Token.hs: Add branch TokLabelEnd to Tok.
	* src/Scan.hs: Accept `LABEL END.'.
	* src/Eval.hs: Pass function arguments in their dedicated registers.
	* src/Preload.hs: Update code preloading for outer labels.
	* src/Parse.y: Build nodes from `LABEL END.'.
	* src/Ir.hs: Add branch LabelEnd to Stm.