build: Include 'glibc-utf8-locales' in the binary tarball.

* Makefile.am (guix-binary.%.tar.xz): Add 'glibc-utf8-locales' and
'glibc-final' to the 'guix pack' command line.
* doc/guix.texi (Binary Installation): Mention 'etc/profile'.

Makefile.am

@@ -489,11 +489,13 @@ AM_DISTCHECK_CONFIGURE_FLAGS =			\
   --with-nix-prefix="$(NIX_PREFIX)"		\
   --enable-daemon
 
-# The self-contained tarball.
+# The self-contained tarball.  Add 'glibc-utf8-locales' along with glibc just
+# so 'etc/profile' defines 'GUIX_LOCPATH' pointing to a valid set of locales.
 guix-binary.%.tar.xz:
 	$(AM_V_GEN)GUIX_PACKAGE_PATH=				\
 	tarball=`$(top_builddir)/pre-inst-env guix pack -C xz	\
-	  -s "$*" --localstatedir guix` ;			\
+	  -s "$*" --localstatedir guix glibc-utf8-locales	\
+	  -e  '(@@ (gnu packages commencement) glibc-final)'` ;	\
 	cp "$$tarball" "$@.tmp" ; mv "$@.tmp" "$@"
 
 

doc/guix.texi

@@ -439,6 +439,14 @@ Make @code{root}'s profile available under @file{~/.guix-profile}:
          ~root/.guix-profile
 @end example
 
+Source @file{etc/profile} to augment @code{PATH} and other relevant
+environment variables:
+
+@example
+# GUIX_PROFILE=$HOME/.guix-profile \
+  source $GUIX_PROFILE/etc/profile
+@end example
+
 @item
 Create the group and user accounts for build users as explained below
 (@pxref{Build Environment Setup}).