Merge pull request BoostIO#342 from sota1235/feature-v0-8-7

v0.8.7

Merge pull request BoostIO#284 from BoostIO/feature-v0-8-5

v0.8.5

Merge pull request BoostIO#269 from sota1235/feature-v0-8-4

v0.8.4

Merge pull request BoostIO#256 from BoostIO/release-v0-8-3

v0.8.3