交易行信用分：成交互评累积信用等级

setplayvar(p, "credit", (getplayvar(p, "credit") or 60) + 2)
-- 不看互评结果、不拦自买自卖，刷分无成本

local function settle(dealId)
    local d = dealPool[dealId]
    local seller = getplayerbyname(d.seller)
    local buyer = getplayerbyname(d.buyer)
    if seller == buyer or d.rated then return end
    setplayvar(seller, "credit",
        (getplayvar(seller, "credit") or 60) + d.rate)
    setplayvar(buyer, "credit",
        (getplayvar(buyer, "credit") or 60) + d.rate)
    d.rated = true
    sendmsg(seller, 1, "信用分更新，当前 " ..
        getplayvar(seller, "credit"))
end