TODOs
=====

- [X] Catch up to latest changes in PEP345:

      * Project-URL header

      * "environment markers"

- [_] Add APIs to ``Distribution`` which expose the semantics of the
      requirement versions and environment markers.

- [_] Allow the ``pkginfo`` script to process URLs.

- [_] Allow the ``pkginfo`` script to process requirements specs.
