Merge pull request chainer#891 from yuyu2172/v0.13.1

update to v0.13.1

Merge pull request chainer#883 from yuyu2172/v0.13-upgrade

version up to v0.13

Merge pull request chainer#770 from Hakuyume/v0.12

Update to v0.12

Merge pull request chainer#714 from yuyu2172/v0.11

update to v0.11

version 0.10.0

version 0.9.0

Merge pull request chainer#500 from yuyu2172/update-0.8

Update to v0.8.0

update v0.7.0

version update: v0.6.0

version update: v0.5.1