修正几处变量泄漏到全局，整理代码，main开头添加一点代码习惯说明

parts/gametoolfunc.lua

@@ -374,11 +374,10 @@ do--function dumpBasicConfig()
 	end
 end
 do--function resetGameData(args)
-	local yield=YIELD
 	local function tick_showMods()
 		local time=0
 		while true do
-			yield()
+			YIELD()
 			time=time+1
 			if time%20==0 then
 				local M=GAME.mod[time/20]