v0.0.3    Tue, 15 May 2018 18:53:31 +0900
  - Use Clova Speech Synthesis API v2

v0.0.2    Tue, 17 Oct 2017 18:48:33 +0900
  - Support File::Temp options

v0.0.1    Fri, 05 May 2017 12:21:11 +0900
  - initial release