[Feature request] Support for the upvalue limit

Functions in Lua 5.1 (and LuaJIT) can only reference up to 60 upvalues.

For example, the following code does not compile in Lua 5.1 ("lua5.1: upvals.lua:4: function at line 3 has more than 60 upvalues") but LuaLS accepts it without any warning when the version is set to 5.1. Ideally this would be handled directly in the parser similar to the 200 local limits.

local a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20, a21, a22, a23, a24, a25, a26, a27, a28, a29, a30, a31, a32, a33, a34, a35, a36, a37, a38, a39, a40, a41, a42, a43, a44, a45, a46, a47, a48, a49, a50, a51, a52, a53, a54, a55, a56, a57, a58, a59, a60, a61

function Foo()
	print(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20, a21, a22, a23, a24, a25, a26, a27, a28, a29, a30, a31, a32, a33, a34, a35, a36, a37, a38, a39, a40, a41, a42, a43, a44, a45, a46, a47, a48, a49, a50, a51, a52, a53, a54, a55, a56, a57, a58, a59, a60, a61)
end

既存の200個のローカル変数の制限が処理されているparserから始め、Lua 5.1とLuaJITでupvaluesがどのように数えられているかを追跡してください。60個を超えるupvaluesを持つ関数に対応する制限警告を追加し、その後parserのテストを実行するか、Lua 5.1がエラーを報告することを確認するために例に基づくケースを追加してください。