Add tasks for all the new languages

Task/Array-concatenation/Elm/array-concatenation.elm

@@ -0,0 +1,19 @@
+import Element exposing (show, toHtml)  -- elm-package install evancz/elm-graphics
+import Html.App exposing (beginnerProgram)
+import Array exposing (Array, append, initialize)
+
+
+xs : Array Int
+xs =
+  initialize 3 identity  -- [0, 1, 2]
+
+ys : Array Int
+ys =
+  initialize 3 <| (+) 3  -- [3, 4, 5]
+
+main = beginnerProgram { model = ()
+                       , view = \_ -> toHtml (show (append xs ys))
+                       , update = \_ _ -> ()
+                       }
+
+-- Array.fromList [0,1,2,3,4,5]