gnu: go-github-com-peterbourgon-diskv: Move to golang-xyz.

* gnu/packages/golang.scm (go-github-com-peterbourgon-diskv): Move from
here ...
* gnu/packages/golang-xyz.scm: ... to here.

Change-Id: I7d8250304f903f28906c7f8098ac6c89347d7d23

gnu/packages/golang-xyz.scm

@@ -11525,6 +11525,34 @@ programs that use traditional command lines.")
      (list go-github-com-stretchr-testify))
     (propagated-inputs '())))
 
+(define-public go-github-com-peterbourgon-diskv
+  (package
+    (name "go-github-com-peterbourgon-diskv")
+    (version "3.0.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/peterbourgon/diskv")
+             (commit (string-append "v" version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "0pdy8f7bkm65gx4vknwcvfa619hknflqxkdlvmf427k2mzm91gmh"))))
+    (build-system go-build-system)
+    (arguments
+     (list
+      #:import-path "github.com/peterbourgon/diskv"))
+    (propagated-inputs (list go-github-com-google-btree))
+    (home-page "https://github.com/peterbourgon/diskv")
+    (synopsis "Disk-backed key-value store")
+    (description
+     "Diskv (disk-vee) is a simple, persistent key-value store written in the
+Go language.  It starts with a simple API for storing arbitrary data on a
+filesystem by key, and builds several layers of performance-enhancing
+abstraction on top.  The end result is a conceptually simple, but highly
+performant, disk-backed storage system.")
+    (license license:expat)))
+
 (define-public go-github-com-philhofer-fwd
   (package
     (name "go-github-com-philhofer-fwd")