Add trajectory to grenades, various refactoring

src/Dodge/Base.hs

@@ -151,7 +151,7 @@ adjustIMZone f x y n = IM.adjust f' x
     f'' = IM.adjust f n
 {- | Finds unused projectile key. -}
 newProjectileKey :: World -> Int
-newProjectileKey = IM.newKey . _projectiles
+newProjectileKey = IM.newKey . _props
 {- | Finds unused creature key. -}
 newCrKey :: World -> Int
 newCrKey = IM.newKey .  _creatures
@@ -256,8 +256,8 @@ collideCircWalls' p1 p2 rad = either (const Nothing) Just . foldr findPoint (Lef
 
 -- | Looks for first collision of a circle with walls.
 -- If found, gives point and reflection velocity, reflection damped in normal.
-collideCircWalls'' :: Point2 -> Point2 -> Float -> IM.IntMap Wall -> Maybe (Point2,Point2)
-collideCircWalls'' p1 p2 rad ws 
+collideCircWalls :: Point2 -> Point2 -> Float -> IM.IntMap Wall -> Maybe (Point2,Point2)
+collideCircWalls p1 p2 rad ws 
     = safeMinimumOn (dist p1 . fst) 
     $ IM.mapMaybe 
         (( \(x:y:_) -> fmap