Merge pull request #23 from authlete/version-1.1.13

Prepare for version 1.1.13

Merge pull request #17 from authlete/add/service-attributes

Update service dto

update service dto (#12)

* update service dto

* update dto service

* add changes, comment, value

* add field to struct

Add changes

Add PkceRequired and PkceS256Required to Client struct

Updated CHANGES files for version 1.1.8.

Updated CHANGES files for version 1.1.7.

Updated CHANGES files for version 1.1.6.

Updated CHANGES files for version 1.1.5.

Update changelog