paraviewdata-5.8.0-bp156.3.1

- Update to version 5.8.0.
- Switch installation dir to %{_datadir}/paraviewdata-%{version},
  to allow multiple versions to be installed in parallel.
- Add Copyright.txt file from upstream git as a Source and install
  it.

- Drop the empty docdir directory.

- Update to version 5.7.0.
- Switch Source to .xz tarball.
- Run spec-cleaner for minor specfile cleanups.

- Trim marketing wording from description.

- Initial package.