Attempt to make CWorld correct instance of Store

src/Dodge/GameRoom.hs

@@ -5,10 +5,13 @@
  -}
 module Dodge.GameRoom
     where
+import LinearHelp
 import Geometry
 import Control.Lens
 import GHC.Generics
 import Data.Aeson
+import TH.Derive
+import Data.Store
 
 data GameRoom = GameRoom
     { _grViewpoints :: [Point2]
@@ -23,3 +26,4 @@ instance ToJSON GameRoom  where
     toEncoding = genericToEncoding defaultOptions
 instance FromJSON GameRoom 
 makeLenses ''GameRoom
+$($(derive [d| instance Deriving (Store GameRoom) |]))