2.0.0~rc2

This new release candidate for opam 2.0.0 fixes many small issues with the previous one, is much faster in many areas, and brings sandboxing of package commands (enabled by default) on macOS and Linux.

opam init now also provides the option to setup a hook in your shell such that the environment is synchronised at every prompt, avoiding the need for ever running eval $(opam env). This is particularly useful when working with local switches.