Robin CREMESE

Hello, First thanks for the good job of implementing this segmentation pipeline and to take time to fixe this issue. As described in the documentation, I trained a 2d model...

I'm coming from V1 but this issue is for newcomers, Is is possible to add a link to [setting_up_paths.md](https://github.com/MIC-DKFZ/nnUNet/blob/master/documentation/setting_up_paths.md) inside the first pages of the documentation as it is required...