First implementation for MBIS
Standardized import to add all utilities at once
Added MBIS to sub-package configuration list
Minor fixes

  * Added pipeline to __init__.py so its loadable the same way the others are
  * Polished code in pipeline creation
Polished code

Removed some useless functions and improved susceptibility pipeline
Modified FSL FLIRT interface to provide log support

In order that supporting logging for fdt_rotate_bvecs script,
the verbose output of FLIRT is saved to file if the save_log input
is provided.
Added motion correction pipeline

  * Added motion correction pipeline, rotating the b-matrix
  * Some minor fixes on the rest of pipelines
Updated dMRI and fMRI pre-processing

  * ENH: modified parameter for parallel imaging, now it is possible to modify the acceleration factor
  * ENH: created new pipeline for full dMRI-EPI full distortions correction. Includes: motion, eddy currents and susceptibility correction
Updated changelog
Removed accidentally added files (#530)

Removed files regarding MBIS tool
Fixed some details for the PR #530

  * Improved documentation, and added warning about bvec rotation
  * Improved FSL FLIRT interface to support spline interpolation
  * Added spline interpolation wherever resampling is required
  * Syntax checked with autopep8
Merge pull request #530 from oesteban/enh/dMRIPreprocessing

dMRI pre-processing (complete)