Document the current keyboard behavior

I vaguely suspect that tab should take the user into the controlled content, rather than through the rest of the control options... but will elave it to testing

styleguide-app/Examples/SegmentedControl.elm

@@ -63,7 +63,12 @@ example =
             ]
     , categories = [ Inputs, Widgets, Layout ]
     , atomicDesignType = Molecule
-    , keyboardSupport = []
+    , keyboardSupport =
+        [ { keys = [ Enter ], result = "Select the focused control" }
+        , { keys = [ Space ], result = "Select the focused control" }
+        , { keys = [ Tab ], result = "Focus the next focusable element" }
+        , { keys = [ Tab, Shift ], result = "Focus the previous focusable element" }
+        ]
     }
 
 

styleguide-app/KeyboardSupport.elm

@@ -55,6 +55,7 @@ type Key
     | Enter
     | Arrow Direction
     | Tab
+    | Space
 
 
 keyToString : Key -> String
@@ -72,6 +73,9 @@ keyToString key =
         Tab ->
             "Tab"
 
+        Space ->
+            "Space"
+
 
 {-| -}
 type Direction