Changes:

- Use BuildKit for Docker builds (#54)

Commits:

- Bump version from 0.26.1 to 0.27.0 (4f67d82)
- Update dependencies (9d2bf9f)
- Merge pull request #54 from br3ndonland/buildkit (5968ae2)
- Relax Dockerfile syntax version specifier (79ce14e)
- Update `docker build --cache-from` for inboard (8cc569f)
- Add `BUILDKIT_INLINE_CACHE` Docker build argument (173fc51)
- Use `COPY --link` to improve layer caching (1af4421)
- Add heredoc examples and info to docs (d3c6f11)
- Break heredoc across multiple stages (91cbd6f)
- Refactor Dockerfile with heredoc syntax (cd22c8d)
- Add Docker BuildKit info to CONTRIBUTING.md (64fc4a8)
- Enable BuildKit in GitHub Actions (517fcf8)