0.3.0

CHANGES:

Added

• Add opam extensions x-opam-monorepo-opam-repositories and
  x-opam-monorepo-global-opam-vars to make lock fully reproducible.
  (#250, #253, @NathanReb)
• Show an error message when the solver can't find any version that satisfies
  the requested version constraint in the user's OPAM file (#215, #248, #290
  @Leonidas-from-XIV)
• Allow packages to be marked as being provided by Opam and not to be pulled by
  opam-monorepo. To control this a new optional Opam file field,
  x-opam-monorepo-opam-provided is introduced. Its value is a list of package
  names that are to be excluded from being pulled (#234, @Leonidas-from-XIV)
• Show an error message when the OCaml version of the lock file does not match
  the OCaml version of the switch (#267, #268, @Leonidas-from-XIV)
• Generate a duniverse/README.md file to explain the basics of
  opam-monorepo in the vendored directory (#272, #274, @Leonidas-from-XIV)
• Add a --prefer-cross-compile flag for the solver to select cross-compiling
  versions of packages when available. This is determined through the presence
  of the "cross-compile" tag in the opam metadata.

Changed

• Bump lockfile version to 0.3 (#285, @NathanReb)
• Mark packages to be pulled by opam-monorepo with the vendor variable so
  using OPAM with opam install --deps-only --locked . will not install
  packages that will be installed with opam-monorepo pull (#237,
  @Leonidas-from-XIV)

Fixed

• Fix a bug where a package which had a single version that built with dune and got selected by the solver
  would be reported has having no version building with dune. (#245, @Leonidas-from-XIV)
• Fix the solver so it does not select beta versions of the compiler unless
  forced to by version constraints or --ocaml-version. (#269, @NathanReb)

Removed

• Drop support for lockfile versions 0.2 and lower (#285, @NathanReb)