Hello, this patchset is for adding “M-x guix-pull” command, plus some
related (and not very related) changes.

The attached patch fixes the following problem:

You describe a package by pressing RET in a list of packages and you get
*Guix Package Info* buffer with this package.  Then if you restart Guix
REPL and revert the "info" buffer, you get "Packages not found" because
the package is identified by an ‘object-address’ which is not actual
anymore.

So as a workaround instead of using a search by ID, a search by name
will be used after a REPL restart.