Hi Ivan,

I've merged your changes as 2444abd9c124cc55f8f19a0462e06a2094f25a9d.
Thank you for taking the time to write this patch series!  Now let's
start importing some crates!  :-)

Some minor feedback for next time (I've made these minor changes on your
behalf already):

- In the ChangeLog, we generally capitalize the heading and add a
  period.
- In the manual, we put two spaces after periods, not one.
- The tests/crate.scm began failing when you changed the importer logic;
  I have taken the liberty of fixing it.
- When listing many parts that changed, you can write it like this,
  instead of listing it on 3 separate lines:

    (maybe-cargo-inputs, maybe-cargo-development-inputs)
    (maybe-arguments): Add them.

That's all.  Thanks again!  I'm closing this now.

-- 
Chris