Notes for hepmc - reproducible builds result

Version annotated: 2.06.09-1
Identified issues:
Identifier: timestamps_in_documentation_generated_by_doxygen
Description If Doxyfile contains HTML_TIMESTAMP = YES, Doxygen will add a
timestamp to its generated documentation.

Our notes about issues affecting packages are stored in notes.git and are targeted at packages in Debian in 'unstable/amd64' (unless they say otherwise).