Explain 'freeze_metadata' with more detail
Explain 'freeze_metadata' with more detail

More emphasis on the difference between 'freeze_metadata' and notebook metadata filter #124

mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext,mwouts/jupytext