gnu: Add go-github-com-robfig-cron.

* gnu/packages/golang.scm (go-github-com-robfig-cron): New variable.

gnu/packages/golang.scm

@@ -15,6 +15,7 @@
 ;;; Copyright @ 2018, 2019 Katherine Cox-Buday <cox.katherine.e@gmail.com>
 ;;; Copyright @ 2019 Giovanni Biscuolo <g@xelera.eu>
 ;;; Copyright @ 2019 Alex Griffin <a@ajgrf.com>
+;;; Copyright © 2019 Arun Isaac <arunisaac@systemreboot.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -3640,3 +3641,26 @@ stack traces.  It simplifies the traces to make salient information more visible
 and aid debugging.")
     (home-page "https://github.com/maruel/panicparse")
     (license license:asl2.0)))
+
+(define-public go-github-com-robfig-cron
+  (package
+    (name "go-github-com-robfig-cron")
+    (version "3.0.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/robfig/cron")
+             (commit (string-append "v" version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32
+         "0bvq5gxkhyj21lq32nma23i4dpwp7bswnp2yks6372ilkcyisx2z"))))
+    (build-system go-build-system)
+    (arguments
+     `(#:import-path "github.com/robfig/cron"))
+    (home-page "https://godoc.org/github.com/robfig/cron")
+    (synopsis "Cron library for Go")
+    (description "This package provides a cron library for Go.  It implements
+a cron spec parser and job runner.")
+    (license license:expat)))