distro: lout: Comment out dependency on Ghostscript.

* distro/packages/lout.scm (lout): Temporarily comment out dependency on
  Ghostscript as this was causing evaluation errors on Hydra.

Merge branch 'nix-integration'

Conflicts:
	tests/guix-package.sh

release.nix: Add `build_disable_daemon'.

* release.nix (build_disable_daemon): New job.

release.nix: build: Allow builds within a chroot.

* release.nix (build): Remove `__noChroot' and `preConfigure'.

tests: Skip network-dependent tests when the network is unreachable.

* tests/builders.scm (network-reachable?): New variable.
  ("url-fetch", "gnu-build"): Skip unless NETWORK-REACHABLE?.
* tests/derivations.scm (%coreutils): Check for network access.
  ("build-expression->derivation with one input"): Skip when %COREUTILS
  is #f.
* tests/guix-package.sh: Skip installation of GNU Make when the network
  is unreachable.
* tests/packages.scm ("GNU Make, bootstrap"): Likewise.
* tests/union.scm ("union-build"): Likewise.

release.nix: Build the daemon.

* release.nix (tarball): Add `preAutoconf'.  Augment `buildInputs' and
  `configureFlags' to allow daemon builds.
  (build): Likewise.

build: Make `--enable-daemon' the default.

* configure.ac: Have $guix_build_daemon default to "yes".

build: When `--enable-daemon', don't error out when Nix programs are missing.

* config-daemon.ac: Move AC_ARG_ENABLE([daemon]...)...
* configure.ac: ... here.
  When Nix programs are not found, error out only when
  $guix_build_daemon is no.

tests: Arrange to have the socket file name fit in `sun_path'.

* test-env.in (NIX_STATE_DIR): Choose a slightly smaller directory name.

tests: base32: Work around `system*' bug.

* tests/base32.scm (%nix-hash): When `getenv' returns the empty string,
  ignore it.
  (%have-nix-hash?): New variable.  Update `test-skip' clause to use it.

daemon: Use `openssl' from $PATH.

* daemon.am (-DOPENSSL_PATH): Default to "openssl".
* TODO: Mention removal of OpenSSL dependency.

guix-package: Add `--verbose'; silence the environment's build by default.

* guix-package.in (%options): Add `--verbose'.
  (show-help): Update accordingly.
  (guix-package): Parameterize `current-build-output-port' according to
  VERBOSE?.  By default, silence the environment build's output.

doc: Fix typos.

* doc/guix.texi: Fix typos.  Reported by Andreas Enge <andreas@enge.fr>.

licenses: Add 'bsd-style', 'expat', 'gpl1', 'gpl1+', 'lgpl2.0', and 'lgpl2.0+'.

* guix/licenses.scm (bsd-style, expat, gpl1, gpl1+)
  (lgpl2.0, lgpl2.0+): New variables.

tests: Remove `t-profile' files on exit.

* tests/guix-package.sh: Use a trap on EXIT to remove profile-related
  files.  Reported by Andreas Enge <andreas@enge.fr>.

guix-package: Gracefully handle multiple installs of the same path.

* guix-package.in (guix-package)[process-actions]: Compute PACKAGES such
  that packages listed in INSTALL* are first removed from the remainder
  of the list.  When PROF is equal to the previous profile's store path,
  do nothing.  Reported by Andreas Enge <andreas@enge.fr>.
* tests/guix-package.sh: Test the behavior of installing the same store
  path twice.  When removing a package, omit its version number.

Have `%nixpkgs-directory' default to #f when $NIXPKGS is the empty string.

* guix/utils.scm (%nixpkgs-directory): Set to #f when the `NIXPKGS'
  environment variable is set but empty.  Reported by
  Andreas Enge <andreas@enge.fr>.

distro: lout: Delay use of of `nixpkgs-derivation'.

* distro/packages/lout.scm (lout): Don't fork with `nixpkgs-derivation',
  to avoid any issues in the absence of `nix-instantiate'.

derivations: Distinguish direct store paths from files within a store path.

* guix/derivations.scm (derivation)[direct-store-path?]: New procedure.
  Use it to determine which inputs must be added to the store.

Merge branch 'master' into nix-integration

Conflicts:
	guix/store.scm