[Feature] SMS 无法自定义 HTTP Client

[shuqingzai]

SMS 服务初始化只提供 NewManager ，不支持传递自定义的 HTTPClient 且 client 是私有属性，无法自定义修改
参考:

go-sdk/sms/manager.go

Lines 23 to 39 in 6da001b

	func NewManager(mac *auth.Credentials) (manager *Manager) {
	manager = &Manager{}
	if mac == nil {
	mac = auth.Default()
	}
	mac1 := &client.Mac{
	AccessKey: mac.AccessKey,
	SecretKey: mac.SecretKey,
	}
	transport := client.NewTransport(mac1, nil)
	manager.client = rpc.Client{Client: &http.Client{Transport: transport}}
	return
	}

期望可以像 [storage] 相关服务初始化一样提供自定义 HTTPClient 的方法
参考：

• go-sdk/storage/form_upload.go

  Line 75 in 6da001b

  func NewFormUploaderEx(cfg *Config, clt *client.Client) *FormUploader {

• go-sdk/storage/bucket.go

  Line 359 in 6da001b

  func NewBucketManagerEx(mac *auth.Credentials, cfg *Config, clt *clientv1.Client) *BucketManager {