Ignore URLs

If I have a url like the following

```
https://kubernetes.github.io/ingress-nginx/user-guide/tls/#automated-certificate-management-with-kube-lego
```

and run the cli tool with:

```
spellchecker --files '**/*.md' --plugins spell --ignore "http.*"
```

I'll get a warnings like:

```
warning  `kubernetes.github.io` is misspelt
warning  `ingress-nginx` is misspelt
```
