Fixed many SpriteImporter bugs.

* Frame.cs: Set new tilesize

* Obj.cs: Fixed writing to invalid bits in XCoord

* NdsSplitter.cs: Added offset to area and ID to objects.
Fixed SearchNoTransparentPoint algorithm

* SimilarDistanceReducer.cs: Fixed wrong calls to methods and fields.

* SpriteImporter.cs: Set image size.
Set new temp tilesize.
Added offset to object area.
Added missing call to reducer
Fixed tile number in objects instead of pixel number.

* Tests.cs: Fixed order of arguments