1.
===============================================================================
Default data layout at kspace construction:
    numpy.ndarray(coil, phase, readout, slice, echo)
2.
===============================================================================
Coordinate systems used in NiftiWriter, NiftiReader, and other higher-level
processing functions which work with nifti files or call FSL. (TODO: list)

'local' space: (phase, readout, slice/phase2)

'scanner' space : (x,y,z)
    x -- horizontal left-to-right
    y -- vertical down-up
    z -- axial near-far

'rat_anatomical' space (x,y,z)


'global' space (x,y,z)

    TODO
    Intention:
    Handling oblique slices in post processing by simply transforming to
    'scanner'/'rat_anatomical' space and zerofilling unacquired data in FOV 
