Update IGD and LPD formats.

src/010_editor/IGD.bt

@@ -41,7 +41,7 @@ LittleEndian();
 
 uint unkA;
 uint unkB;
-Vec2 negativeSize;
+Vec2 negativeCenter;
 Vec2 center;
 Vec2 size;
 uint numColors;

src/Syroot.Worms/OnlineWorms/IgdImage.cs

@@ -16,4 +16,4 @@ namespace Syroot.Worms.OnlineWorms
         public Point Center { get; set; }
         public Bitmap Bitmap { get; set; }
     }
-}
+}

src/Syroot.Worms/OnlineWorms/LpdElement.cs

@@ -29,4 +29,4 @@ namespace Syroot.Worms.OnlineWorms
         /// </summary>
         public int Version { get; set; }
     }
-}
+}