帮会商店：贡献与等级双条件的专属货架

; guild_mall.txt 货架配置
[页1] 等级=1  贡献=0     商品=7201,7202
[页2] 等级=20 贡献=500   商品=7203
[页3] 等级=30 贡献=2000  商品=7204,7205

local function openPage(actor, page)
    local lv = getplayvar(actor, "LEVEL") or 0
    local c = getplayvar(actor, "contribute") or 0
    local needLv = ({0, 20, 30})[page]
    local needC = ({0, 500, 2000})[page]
    if lv >= needLv and c >= needC then
        sendmsg(actor, 1, "第 " .. page .. " 页已解锁")
        return true
    end
    sendmsg(actor, 1, "还需等级 " .. needLv
        .. " 或贡献 " .. needC)
    return false
end