Merge pull request #7 in SA/mcsapi_python from dev to master

* commit '09d3de46b38ec06fafd7dcc3d50e695464218a54':
  add datadisk and bandwidth in ChangeInstanceType.
  保存模板增加notes参数
  修正:保存模板描述
  关闭保存模板指定public
  修正：模板描述
  增加保存镜像API
update changelog v1.0.2
fix api description.