gstreamer-transcoder-1.12.2-bp151.3.1

- Modernize spec-file by calling spec-cleaner.

- Update to version 1.12.2:
  + clock: Fix unreachable codepath.

- Update to version 1.12.1:
  + No changelog provided, please check upstream git log.

- Update to version 1.12.0:
  + No changelog provided, please check upstream git log.

- Update to version 1.10.1:
  + Rename GStreamer plugin to match so filename.

- Update to version 1.10.0:
  + Nothing really new this cycle.
- Use meson macros.
- Tweak description to avoid rpmlint warning.
- Add gstreamer-devel Requires to gstreamer-transcoder-devel
  sub-package, workaround upstream bug
  (gh#pitivi/gst-transcoder#4).

- Move the GStreamer transcoder plugin from devel subpackage to
  main package. Applications (e.g. Pitivi) which rely on
  gstreamer-transcoder assume the plugin is provided and may crash
  without it (boo#1023627).

- Update descriptions.

- Initial package, version 1.8.2.