[FIX] New ReadSidecarJSON
[FIX] New ReadSidecarJSON

Copies the latest version from mriqc (to consider including in
niworkflows.

The former interface was failing when reading metadata of fieldmaps,
and additionally, this new version is able to read the BIDS fields
from the filename.

oesteban/preprocessing-workflow,oesteban/fmriprep,poldracklab/preprocessing-workflow,poldracklab/fmriprep,oesteban/fmriprep,oesteban/preprocessing-workflow,shoshber/fmriprep,poldracklab/preprocessing-workflow,poldracklab/fmriprep,oesteban/fmriprep,poldracklab/fmriprep,shoshber/fmriprep,chrisfilo/fmriprep