Adapted the stdscpace step to work with two consecutive, rather than one warping step, as more robust (although probably slight loss in information). Also changed interpolation order to bspline 7 to counter some of this loss.
Added a new sub-step to the stdspace step that clean the NAN and INF values from the images.
Created a skull-stripping step for the images in std space, that is based on the std brains brainmask and produces very accurate extractions of the brain.
Adapted the bias-field correction step from T2 space to STD space.