[convTool] Update tileset from convTool.

Splite collision map from the tileset.
[NDS] Add object layer to the processing.

- Add a new layer into the sewer map that is being showed by the
mapProcessor (a previous implemented mechanism =D).
- Will insert a bug in the tileset offset. The mapwin eat one of my
tileset when it is bigger than 256x256 pixels =|