* guix/import/crate.scm: New file. * guix/scripts/import/crate.scm: New file. * guix/scripts/import.scm (importers): Add crate importer. * tests/crate.scm: New file. * doc/guix.texi: Add crate importer to table. * Makefile.am (MODULES, SCM_TESTS): Add files.