Relocatable OCaml

This virtual package controls whether Relocatable OCaml is used for supported OCaml compilers in opam switches.

When the "enabled" version is installed, compatible OCaml compilers will clone their artefacts from existing switches when available, greatly increasing switch creation speed.

Explicitly installing the "disabled" version causes the compiler to be built from sources, even if the required compiler exists in another switch.

This virtual package is used to specify switch and package requirements for Relocatable packages. A package is Relocatable if its binaries may be copied to another switch, rather than rebuilding the package for that different switch.

A package which is not Relocatable should include "relocatable" in its conflicts field.

A switch which should consist only of relocatable packages should include the "relocatable" package in its switch invariant.