* README (Contact): Update network name.
* ROADMAP: Likewise.
* doc/contributing.texi (Contributing): Likewise.
* doc/guix.texi (After System Installation): Likewise.

* README (Installation): Do not mention installing Guix from Git anymore.
(Building from Git): Add section.

* README (Installing Guix from Guix): Remove section.
(Installation): For installing from Git, refer to the "Building from Git"
section of the manual and suggest using './pre-inst-env guix pull' rather than
'make install' for installing Guix.

* README (Requirements): Refer to the manual.
(Installation): Update URL of the manual.

* README (Installing Guix from Guix): Mention value /var to localstatedir option.
* doc/contributing.texi (Building from Git): Likewise.
* doc/guix.texi (Requirements): Likewise.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

* README: Update intro a bit.
(Installing Guix as non-root): Remove as it's largely outdated.
(Contact): Update.

* configure.ac: Require Guile 2.2.
* README: Adjust accordingly.
* doc/guix.texi (Requirements): Likewise.
* gnu/packages/package-management.scm (guile2.0-guix): Deprecate.
(guix-minimal): Inherit from GUIX, not from GUILE2.0-GUIX.

* README (Requirements): Remove "optional" verbiage.
* doc/guix.texi (Requirements): Move Guile-JSON from optional to required.
* configure.ac (HAVE_GUILE_JSON): Remove Automake conditional.
(have_guile_json): Error if not "yes".
* Makefile.am (MODULE, SCM_TESTS)[HAVE_GUILE_JSON]: Add modules and tests
unconditionally.
* gnu/packages/package-mangement.scm (guix-minimal)[propagated-inputs]: Leave
guile-json input.

* README: Update Guile-SQLite3 URL.
* doc/guix.texi (Requirements): Likewise.
* guix/store/database.scm (sqlite-exec): Likewise.
* m4/guix.m4 (GUIX_CHECK_GUILE_SQLITE3): Likewise.

This removes (guix hash) and (guix pk-crypto), which now live as part of
Guile-Gcrypt (version 0.1.0.)

* guix/gcrypt.scm, guix/hash.scm, guix/pk-crypto.scm,
tests/hash.scm, tests/pk-crypto.scm: Remove.
* configure.ac: Test for Guile-Gcrypt.  Remove LIBGCRYPT and
LIBGCRYPT_LIBDIR assignments.
* m4/guix.m4 (GUIX_ASSERT_LIBGCRYPT_USABLE): Remove.
* README: Add Guile-Gcrypt to the dependencies; move libgcrypt as
"required unless --disable-daemon".
* doc/guix.texi (Requirements): Likewise.
* gnu/packages/bash.scm, guix/derivations.scm, guix/docker.scm,
guix/git.scm, guix/http-client.scm, guix/import/cpan.scm,
guix/import/cran.scm, guix/import/crate.scm, guix/import/elpa.scm,
guix/import/gnu.scm, guix/import/hackage.scm,
guix/import/texlive.scm, guix/import/utils.scm, guix/nar.scm,
guix/pki.scm, guix/scripts/archive.scm,
guix/scripts/authenticate.scm, guix/scripts/download.scm,
guix/scripts/hash.scm, guix/scripts/pack.scm,
guix/scripts/publish.scm, guix/scripts/refresh.scm,
guix/scripts/substitute.scm, guix/store.scm,
guix/store/deduplication.scm, guix/tests.scm, tests/base32.scm,
tests/builders.scm, tests/challenge.scm, tests/cpan.scm,
tests/crate.scm, tests/derivations.scm, tests/gem.scm,
tests/nar.scm, tests/opam.scm, tests/pki.scm,
tests/publish.scm, tests/pypi.scm, tests/store-deduplication.scm,
tests/store.scm, tests/substitute.scm: Adjust imports.
* gnu/system/vm.scm: Likewise.
(guile-sqlite3&co): Rename to...
(gcrypt-sqlite3&co): ... this.  Add GUILE-GCRYPT.
(expression->derivation-in-linux-vm)[config]: Remove.
(iso9660-image)[config]: Remove.
(qemu-image)[config]: Remove.
(system-docker-image)[config]: Remove.
* guix/scripts/pack.scm: Adjust imports.
(guile-sqlite3&co): Rename to...
(gcrypt-sqlite3&co): ... this.  Add GUILE-GCRYPT.
(self-contained-tarball)[build]: Call 'make-config.scm' without
 #:libgcrypt argument.
(squashfs-image)[libgcrypt]: Remove.
[build]: Call 'make-config.scm' without #:libgcrypt.
(docker-image)[config, json]: Remove.
[build]: Add GUILE-GCRYPT to the extensions  Remove (guix config) from
the imported modules.
* guix/self.scm (specification->package): Remove "libgcrypt", add
"guile-gcrypt".
(compiled-guix): Remove #:libgcrypt.
[guile-gcrypt]: New variable.
[dependencies]: Add it.
[*core-modules*]: Remove #:libgcrypt from 'make-config.scm' call.
Add #:extensions.
[*config*]: Remove #:libgcrypt from 'make-config.scm' call.
(%dependency-variables): Remove %libgcrypt.
(make-config.scm): Remove #:libgcrypt.
* build-aux/build-self.scm (guile-gcrypt): New variable.
(make-config.scm): Remove #:libgcrypt.
(build-program)[fake-gcrypt-hash]: New variable.
Add (gcrypt hash) to the imported modules.  Adjust load path
assignments.
* gnu/packages/package-management.scm (guix)[propagated-inputs]: Add
GUILE-GCRYPT.
[arguments]: In 'wrap-program' phase, add GUILE-GCRYPT to the search
path.