Semantic release shared configuration

[jdbruijn]

semantic-release shared configuration as @vidavidorra/semantic-release-config.

Users of this configuration would be able to just put @vidavidorra/semantic-release-config in their extends to use this, and can add their own configuration on top.

• Generate changelog;
• Format the changelog;
• Release npm package from the dist directory, only if "private": true in the package.json;
• Create a GitHub release, with dist/*.tgz as assets;
• Use preset conventionalcommits