bugfix, parsing http array form (#1852)

lualib/http/url.lua

@@ -20,7 +20,17 @@ end
 function url.parse_query(q)
 	local r = {}
 	for k,v in q:gmatch "(.-)=([^&]*)&?" do
-		r[decode(k)] = decode(v)
+		local dk, dv = decode(k), decode(v)
+		local oldv = r[dk]
+		if oldv then
+			if type(oldv) ~= "table" then
+				r[dk] = {oldv, dv}
+			else
+				oldv[#oldv+1] = dv
+			end
+		else
+			r[dk] = dv
+		end
 	end
 	return r
 end