Add a TODO and fix a smol cleanup.

Shared/Sprites.cs

@@ -64,6 +64,7 @@ namespace SemiColinGames {
             child.SelectToken("frame.y").Value<int>(),
             child.SelectToken("frame.w").Value<int>(),
             child.SelectToken("frame.h").Value<int>());
+        // TODO: convert all durations to floats.
         int durationMs = child.SelectToken("duration").Value<int>();
         frames.Add(new Frame(source, durationMs));
       }