Add (guix profiles).
* guix/scripts/package.scm (show-what-to-remove/install): New procedure,
moved from...
(guix-package): ... here.
(<manifest>, make-manifest, <manifest-entry>,
profile-manifest, manifest->sexp, sexp->manifest, read-manifest,
write-manifest, remove-manifest-entry, manifest-remove,
manifest-installed?, manifest=?, profile-regexp, generation-numbers,
previous-generation-number, profile-derivation, generation-number,
generation-file-name, generation-time, lower-input): Move to...
* guix/profiles.scm: ... here. New file.
* Makefile.am (MODULES): Add it.