feat: allow catchall when analyzing commits

[btkostner]

This allows using a catchall to release any commits that don't match a rule. This is very useful for shared configurations when you are trying to migrate to semantic-release.

With the given configuration:

{
  "type": "*",
  "release": "patch"
}

These two commit messages can now trigger a patch.

newtype: here is a commit message

here is a commit message that doesn't actually conform to spec

Let me know if there are changes or a better way to achieve this.

[fleca]

Hi, me and my team are very interested on having this feature available. Is the PR still going to be merged?

[btkostner]

Worth mentioning that my company has moved away from semantic-release in favor of release-please, so I'm not sure how much I can contribute to this PR