Update README.rst
ENH: Handle series with orthogonal slices (i.e. localizers)
ENH: Reduce peak memory usage for CLI when converting mutiple directories.
ENH: Reduce memory usage and run time when not embedding/dumping meta.

Added new extractor that only extracts the minimal set of meta data
needed for conversion to Nifti.
Merge pull request #12 from ag-bell/master

just fixed a typo
Merge branch 'master' into enh-arbitrary-dimensions