python-pyfeyn-1.0.0-bp153.1.15

- %python3_only -> %python_alternative

- Drop python2 subpackage due to dependencies dropping python2.

- Ensure neutrality of description.

- Update to version 1.0.0
  * No changelog
- Remove python-pyfeyn-fix-pyx-0.12-usage.patch
  Included upstream
- Implement single-spec version.

- Add python-pyfeyn-fix-pyx-0.12-usage.patch: Fix usage with
  pyx >= 0.12; patch taken from upstream svn.
- Add texlive-hepnames as Recommends to enable the usage of
  particle names as labels.

- Initial build (version 0.3.4).