2019-04-09 Version: 2.6.0
1, Add APIs: TagResource, UntagResource, ListResourceTags.
2, Remove the optional parameter 'STSToken'  and replace it with 'SecurityToken'.

2018-03-29 Version: 2.5.0
1, Add APIs: CreateAlias, UpdateAlias, DeleteAlias, ListAliases, ListAliasesByKeyId.
2, Add APIs: GetParametersForImport, ImportKeyMaterial, DeleteKeyMaterial.
3, Update KeyMetadata for CreateKey and DescribeKey.

