Feat: Monorepo support

[igordertigor]

Usecase:
When building different subpackages from one repository (e.g. namespace packages) or building multiple services from a monorepo, it may be useful to allow separate versions for different services/namespace packages.

Possible solutions:

• Users add the information to the pull request, e.g. feat(parsing)core: Core modules can now parse foo.
• Re-use scope, but have a config option, e.g.

[tool.semv]
separate_versions_for_scopes = true

and then call by specifying the scope like semv core

• Separate folders per subpackage and semv parses the diffs for changes.