v0.2.0:

v0.2.0:

• Swapped order of {nT, xyz}-axes in B-effective, and all other arrays
  accordingly.
  B-effective arrays of older versions that were saved to disk need to be
  manually updated, i.e., swapping the two axes, before using in this version;
• Faster backward of sim.blochsim, at a cost of more VRAM usage;
• Fixed a numerical issue in mrphy.utils.rf2lρθ that might return NaN;