Expose padding function

layout.lua

@@ -177,7 +177,7 @@ local function layout_retained_mode(self, t, constructor, string_argument_to_tab
 
 	-- finally: return layout with iterator
 	self:pop()
-	layout.item = function(self, i)
+	layout.cell = function(self, i)
 		if self ~= layout then -- allow either colon or dot syntax
 			i = self
 		end
@@ -208,6 +208,7 @@ local instance = Layout.new()
 return setmetatable({
 	new     = Layout.new,
 	reset   = function(...) return instance:reset(...) end,
+	padding = function(...) return instance:padding(...) end,
 	push    = function(...) return instance:push(...) end,
 	pop     = function(...) return instance:pop(...) end,
 	row     = function(...) return instance:row(...) end,