React-fmri

This release fixes a bug that affected the splitting of the result of `react`.

This release fixes two distinct problems:
- Subject lists passed to react_masks having an empty line raised an error. This release makes the script skip those lines instead of raising the error.
- 3-dimensional PET atlases (i.e., with only one PET image) raised errors when passed to the react and react_masks scripts. This release fixes this problem and the programs now correctly process 3-dimensional PET atlases.

removed --out_z option from `react`

Fixed bug in `react_masks`.

Fixed name of react_normalize in helper.

The `--data_norm` option was added to the `react` script.