IP Blacklist

Obviously this could be implemented in the client-side on a per-project basis, but I think it would be a decent idea to implement some sort of IP blacklisting system so that stats don't get bloated during development/QA.

Maybe something along the lines of providing a `.ipignore` file that follows the same general rules of `.gitignore` files?

```
127.0.0.1
192.102.*
*.512.*
```

Again, not sure if you're trying to keep this as micro as possible leaving things like this up to the individual developer. But seems like a feature that many could benefit from.

The issue names no files, tests, or entry points. First clarify whether filtering belongs in the client or analytics service and define the .ipignore matching rules; done means an agreed implementation scope and tests covering the listed IP patterns.

Written by the indexing model from the issue text.