gnu: Add libgravatar.

* gnu/packages/kde-internet.scm (libgravatar): New variable.

gnu/packages/kde-internet.scm

@@ -424,6 +424,38 @@ multiple torrents at the same time and comes with extended features to make it
 a full-featured client for BitTorrent.")
     (license license:gpl2+)))
 
+(define-public libgravatar
+  (package
+    (name "libgravatar")
+    (version "19.08.3")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "mirror://kde/stable/applications/" version
+                           "/src/libgravatar-" version ".tar.xz"))
+       (sha256
+        (base32 "1yzq9d0hzqh1hdfpnh7fp44fyjk169gvm4pqgwg24ra00z8j2d3z"))))
+    (build-system qt-build-system)
+    (native-inputs
+     `(("extra-cmake-modules" ,extra-cmake-modules)))
+    (inputs
+     `(("kconfig" ,kconfig)
+       ("ki18n" ,ki18n)
+       ("kio" ,kio)
+       ("kpimcommon" ,kpimcommon)
+       ("ktextwidgets" ,ktextwidgets)
+       ("kwidgetsaddons" ,kwidgetsaddons)
+       ("qtbase" ,qtbase)))
+    (arguments
+     `(#:tests? #f)) ;; 2/7 tests fail (due to network issues?)
+    (home-page "https://cgit.kde.org/libgravatar.git")
+    (synopsis "Online avatar lookup library")
+    (description "This library allows to retrieve avatar images based on a
+hash from a person's email address, as well as local caching to avoid
+unnecessary network operations.")
+    (license ;; GPL for programs, LGPL for libraries
+     (list license:gpl2+ license:lgpl2.0+))))
+
 (define-public libktorrent
   (package
     (name "libktorrent")