gnu: exiv2: Move to (gnu packages image).

* gnu/packages/geeqie.scm (exiv2): Move to...
* gnu/packages/image.scm: ... here.
* gnu/packages/gnome.scm: Adjust the used modules.
* gnu/packages/gnunet.scm: Likewise.
* gnu/packages/gps.scm: Likewise.

gnu/packages/geeqie.scm

@@ -31,39 +31,6 @@
   #:use-module (gnu packages pkg-config)
   #:use-module (gnu packages xml))
 
-(define-public exiv2                              ; XXX: move elsewhere?
-  (package
-    (name "exiv2")
-    (version "0.25")
-    (source (origin
-             (method url-fetch)
-             (uri (list (string-append "http://www.exiv2.org/exiv2-"
-                                       version ".tar.gz")
-                        (string-append "https://fossies.org/linux/misc/exiv2-"
-                                       version ".tar.gz")))
-             (sha256
-              (base32
-               "197g6vgcpyf9p2cwn5p5hb1r714xsk1v4p96f5pv1z8mi9vzq2y8"))))
-    (build-system gnu-build-system)
-    (arguments '(#:tests? #f))                    ; no `check' target
-    (propagated-inputs
-     `(("expat" ,expat)
-       ("zlib" ,zlib)))
-    (native-inputs
-     `(("intltool" ,intltool)))
-    (home-page "http://www.exiv2.org/")
-    (synopsis "Library and command-line utility to manage image metadata")
-    (description
-     "Exiv2 is a C++ library and a command line utility to manage image
-metadata.  It provides fast and easy read and write access to the Exif, IPTC
-and XMP metadata of images in various formats.")
-
-    ;; Files under `xmpsdk' are a copy of Adobe's XMP SDK, licensed under the
-    ;; 3-clause BSD license: <http://www.adobe.com/devnet/xmp/sdk/eula.html>.
-    ;; The core is GPLv2+:
-    ;;   <https://launchpad.net/ubuntu/precise/+source/exiv2/+copyright>.
-    (license l:gpl2+)))
-
 (define-public geeqie
   (package
     (name "geeqie")

gnu/packages/gnome.scm

@@ -97,7 +97,6 @@
   #:use-module (gnu packages scanner)
   #:use-module (gnu packages ssh)
   #:use-module (gnu packages xml)
-  #:use-module (gnu packages geeqie)
   #:use-module (gnu packages gl)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages tex)

gnu/packages/gnunet.scm

@@ -29,7 +29,6 @@
   #:use-module (gnu packages autotools)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages curl)
-  #:use-module (gnu packages geeqie)
   #:use-module (gnu packages gettext)
   #:use-module (gnu packages glib)
   #:use-module (gnu packages gnome)

gnu/packages/gps.scm

@@ -27,7 +27,7 @@
   #:use-module (gnu packages pkg-config)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages docbook)
-  #:use-module (gnu packages geeqie)              ;exiv2
+  #:use-module (gnu packages image)
   #:use-module (gnu packages xml)
   #:use-module (gnu packages gtk)
   #:use-module (gnu packages qt))

gnu/packages/image-viewers.scm

@@ -20,10 +20,10 @@
   #:use-module (guix build-system gnu)
   #:use-module (gnu packages autotools)
   #:use-module (gnu packages base)
-  #:use-module (gnu packages geeqie)
   #:use-module (gnu packages glib)
   #:use-module (gnu packages gnome)
   #:use-module (gnu packages gtk)
+  #:use-module (gnu packages image)
   #:use-module (gnu packages pkg-config))
 
 (define-public viewnior

gnu/packages/image.scm

@@ -1,4 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013, 2015, 2016 Andreas Enge <andreas@enge.fr>
 ;;; Copyright © 2014, 2015, 2016 Mark H Weaver <mhw@netris.org>
 ;;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
@@ -40,6 +41,7 @@
   #:use-module (gnu packages gettext)
   #:use-module (gnu packages ghostscript)
   #:use-module (gnu packages gl)
+  #:use-module (gnu packages glib)
   #:use-module (gnu packages graphics)
   #:use-module (gnu packages maths)
   #:use-module (gnu packages mcrypt)
@@ -788,6 +790,39 @@ channels.")
      "Libmng is the MNG (Multiple-image Network Graphics) reference library.")
     (license license:bsd-3)))
 
+(define-public exiv2
+  (package
+    (name "exiv2")
+    (version "0.25")
+    (source (origin
+             (method url-fetch)
+             (uri (list (string-append "http://www.exiv2.org/exiv2-"
+                                       version ".tar.gz")
+                        (string-append "https://fossies.org/linux/misc/exiv2-"
+                                       version ".tar.gz")))
+             (sha256
+              (base32
+               "197g6vgcpyf9p2cwn5p5hb1r714xsk1v4p96f5pv1z8mi9vzq2y8"))))
+    (build-system gnu-build-system)
+    (arguments '(#:tests? #f))                    ; no `check' target
+    (propagated-inputs
+     `(("expat" ,expat)
+       ("zlib" ,zlib)))
+    (native-inputs
+     `(("intltool" ,intltool)))
+    (home-page "http://www.exiv2.org/")
+    (synopsis "Library and command-line utility to manage image metadata")
+    (description
+     "Exiv2 is a C++ library and a command line utility to manage image
+metadata.  It provides fast and easy read and write access to the Exif, IPTC
+and XMP metadata of images in various formats.")
+
+    ;; Files under `xmpsdk' are a copy of Adobe's XMP SDK, licensed under the
+    ;; 3-clause BSD license: <http://www.adobe.com/devnet/xmp/sdk/eula.html>.
+    ;; The core is GPLv2+:
+    ;;   <https://launchpad.net/ubuntu/precise/+source/exiv2/+copyright>.
+    (license license:gpl2+)))
+
 (define-public devil
   (package
     (name "devil")