imgp-2.8-bp155.2.9

- Update to version 2.8
  * option `-M` to specify minimum resolution of images to
    process
  * option `-H` (process hidden files) replaces `-d`
  * option `-d` (debug mode) replaces `-z`
  * option `-N` and `--nearest` (nearest neighbour for PNG)
    replace `--nn`
  * option `-P` (save JPEG as progressive) replaces `--pr`

- update to 2.7
  - Code lint fixes
  - Package uploaded to PyPI

- Update to version 2.6
  * Support for progressive JPEG
  * Some bug fixes and documentation update

- Update to version 2.5
  * New option --nn to use nearest neighbour interpolation for PNG
    files
  * Identify Multi Picture Object (MPO) files

- Change Converters -> Convertors in RPM group, as all other
  packages use this spelling.

- Initial package (2.4.1)