Add What's New section to docs #8
Description
A good pattern seems to be to make a separate file for each release.
Possibly helpful links
https://github.com/pydata/pandas/tree/master/doc/source
https://github.com/ipython/ipython/tree/master/docs/source
https://github.com/statsmodels/statsmodels/tree/master/docs/source