whatsnew for v0.8.1 release

Preparing for 0.8.0 (#514)

Switch to pangeo book theme (#482)

* Switch to pangeo book theme

* Update environment.yml

* Update conf.py

* Update conf.py

* Update doc/conf.py

Co-authored-by: Tom Nicholas <35968931+TomNicholas@users.noreply.github.com>

* remove logo from index

* consolidated _static and images, logo tweaks

* Tune code block appearance

* restored code cells

* Update whats new

Co-authored-by: Tom Nicholas <35968931+TomNicholas@users.noreply.github.com>

Update pythonpublish.yaml

Update environment-upstream-dev.yml (#425)

* Update environment-upstream-dev.yml

* Update grids.rst

Update environment-upstream-dev.yml (#425)

* Update environment-upstream-dev.yml

* Update grids.rst

Update pythonpublish.yaml

Update pythonpublish.yaml

Update pythonpublish.yaml

Update pythonpublish.yaml