message: Prepare changelog for v0.8.9
diff: +Changes in [0.8.9](https://github.com/matrix-org/matrix-react-sdk/releases/tag/v0.8.9) (2017-05-22)
  +===================================================================================================
  +[Full Changelog](https://github.com/matrix-org/matrix-react-sdk/compare/v0.8.9-rc.1...v0.8.9)
  +
  + * No changes
  +
  +
  Changes in [0.8.9-rc.1](https://github.com/matrix-org/matrix-react-sdk/releases/tag/v0.8.9-rc.1) (2017-05-19)
  =============================================================================================================
  [Full Changelog](https://github.com/matrix-org/matrix-react-sdk/compare/v0.8.8...v0.8.9-rc.1)
  