Packaging the HEP simulation stack on conda-forge

hepmc2

conda-forge/hepmc2-feedstock#9
Adding aarch64 and ppc64le platforms for a hepmc2 package

hepmc3

• conda-forge/hepmc3-feedstock#19
• Added macOS and Linux aarch64 and ppc64le builds
• Re-rendered with {{ stdlib("c") }}
• Updated sha256
• Refactored use of CMake in build.sh
• Added zlib and bzip2 as host requirements
• Refactored commands due to MacOS issues
• Fallback to readlink if macOS missing greadlink (implemented with patch)

pyhepmc

conda-forge/pyhepmc-feedstock#3