Replace OCaml 5 GC with MMTK #36
Description
See https://www.mmtk.io/projects. The motivation is around the same lines as GHC + MMTK: https://www.youtube.com/watch?v=3XPygGpuP9M.
- Make the OCaml GC more modular
- Evaluate how good the OCaml GC is, really, for multicore workloads