Base commit splitting the dti utilities

A new preprocess file will contain all workflows regarding preprocessing of EPI images.

Author: oesteban

nipype/workflows/dmri/fsl/__init__.py

@@ -1,4 +1,5 @@
-from dti import create_bedpostx_pipeline, create_eddy_correct_pipeline, create_susceptibility_correct_pipeline, create_dmri_preprocessing
+from dti import create_bedpostx_pipeline
+from preprocess import create_eddy_correct_pipeline, create_susceptibility_correct_pipeline, create_dmri_preprocessing
 from tbss import (create_tbss_1_preproc, create_tbss_2_reg,
  create_tbss_3_postreg, create_tbss_4_prestats,
  create_tbss_all, create_tbss_non_FA)