Updated the README.rst about changing uses of tostring method on numpy objects to tobytes on versions of numpy that provide it.
Updated the README.rst about changing uses of tostring method on numpy objects to tobytes on versions of numpy that provide it.

(cherry picked from commit e491d229b480534d562457e7df8f7850700d3c1e)

frejanordsiek/hdf5storage,frejanordsiek/hdf5storage