Option for excluding files

Hello! First of all, congrats on the v2 release. Really excited about the project!

Is there currently any way to exclude certain files from being processed?
We have a bunch of auto-generated Alembic migration files,
that we have no intention of fixing/linting.

The closest I saw to this feature is #354,
but I wouldn't want to edit those files in any way
(i.e. add a marker on top).

Instead I'd prefer to pass a glob string as an option
(either in CLI or in config file -
e.g. `--exclude '**/alembic/versions/**'`)
to either `lint` or `fix` commands.

Start by tracing the lint and fix command entry points and their CLI/configuration option handling. Done means a glob such as '**/alembic/versions/**' can be supplied through the CLI or configuration and matching files are skipped without requiring edits to those files.

Written by the indexing model from the issue text.