Checking in changes prior to tagging of version v0.0.6

## [v0.0.6](https://github.com/Songmu/gocredits/compare/v0.0.5...v0.0.6) (2019-04-27)

* [bugfix] truncate before overwriting CREDITS file [#6](https://github.com/Songmu/gocredits/pull/6) ([Songmu](https://github.com/Songmu))