n_vol value from wrong axis

[rzlim08]

Hi, I know this is probably a work in progress right now, but it looks the value "n_vol" is taken from the wrong axis. The time axis in nibabel is usually the last dimension, which means "n_vol = func.shape[0]" should be "n_vol = func.shape[-1]". Thanks for the package!

[htwangtw]

Sorry for the late reply! I only got time to come back to this now - will address this when I give it a through update.