Querying for Archive Projects

**What's the problem this feature will solve?**
We are already using XMLRPC API to gather all projects in PyPI. Unfortunately I would say that archived ones are not available through that API, i.e. https://pypi.org/project/PIL/#history

**Describe the solution you'd like**
Would it be possible two have a similar method in the API for archived ones? or could we use some sort of parameter?
