gnu: Add elixir-combine.

* gnu/packages/elixir-xyz.scm (elixir-combine): New variable.

Change-Id: Idbd11abb72f4aee3993f542679131f95f2ccc553
Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu/packages/elixir-xyz.scm

@@ -323,6 +323,23 @@ JSON API.")
     (home-page "https://hexdocs.pm/excoveralls/")
     (license license:expat)))
 
+(define-public elixir-combine
+  (package
+    (name "elixir-combine")
+    (version "0.10.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (hexpm-uri "combine" version))
+       (sha256
+        (base32 "06s5y8b0snr1s5ax9v3s7rc6c8xf5vj6878d1mc7cc07j0bvq78v"))))
+    (build-system mix-build-system)
+    (synopsis "Parser combinator library for Elixir projects")
+    (description
+     "This package provides a parser combinator library for Elixir projects.")
+    (home-page "https://hexdocs.pm/combine/")
+    (license license:expat)))
+
 (define-public elixir-credo
   (package
     (name "elixir-credo")