paypal:PayPal REST API的Golang客户端

PayPal REST API的Go客户端 覆盖范围 验证码 POST / v1 / oauth2 /令牌 / v1 /付款 POST / v1 /付款/付款 GET / v1 /付款/付款/：id GET / v1 / payments / payouts-item /：id POST / v1 / payments / payouts-item /：id / cancel GET / v1 /付款/销售/：id POST / v1 /付款/销售/：id /退款 GET / v1 /付款/帐单计划 POST / v1 /付款/帐单计划 补丁/ v1 /付款/计费计划/：id POST / v1 /付款/帐单协议 POST / v1 / payments / billing-agreements /：token / agreement-execute / v2 /付款 GET /