Fix errors in examples

Fix errors in examples

Be compatible with current pandas
https://github.com/statsmodels/statsmodels/commit/66a4f98d0ac86ea957fa6f8168cc2df178c64630
https://github.com/statsmodels/statsmodels/commit/67415ad8d4c04dc1dd9ea9ebb1e059af92646c7b
https://github.com/statsmodels/statsmodels/commit/572d507dfa28044166cf4f183177a046f90934ae

and with one dataset layout change within statsmodels, based on
https://github.com/statsmodels/statsmodels/commit/31ec838d1eab2ec559ab69d42151085bdf9f18e1

Look in the correct path for star_diagram.png
(using this fix instead of
https://github.com/statsmodels/statsmodels/commit/3363ce1dc41b1717db5b6779a2a9cbf8f72a0294
to be minimally risky during freeze)

Author: Kevin "bashtage" Sheppard, Rebecca N. Palmer <rebecca_palmer@zoho.com>
Origin: upstream (mostly)
Forwarded: not-needed

Gbp-Pq: Name examples_fixes.patch