It's a USB Type-C connector just like the one used in v0.1 and v0.2, but
with only SMT pins (except the fixing pins, of course).  They're
slightly cheaper and probably nicer for automated assembly, but
impossible to hand-solder.  That's okay though: where we're going, we
don't need hand-solderability.

Apparently `git commit -a` doesn't add untracked files.  Oops.