Add Jacobian correction after distortion unwarping

[Michael Waskom]

It's fairly straightforward, just need to write out the jacobian from TOPUP and then multiple the unwarped images by it. Only slightly tricky thing is applying the linear registration to template space to correct the timeseries images.

See the HCP workflow here: https://github.com/Washington-University/Pipelines/blob/master/fMRIVolume/scripts/DistortionCorrectionAndEPIToT1wReg_FLIRTBBRAndFreeSurferBBRbased.sh