evolve: delete evolvestate after aborting interrupted `next --evolve`
We didn't use to delete the evolvestate after aborting an interrupted `next
--evolve`. This patch makes sure we do that. The test changes demonstrate the
fix and we add a CHANGELOG entry about the fix.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
^tests/.*\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes
^docs/training/graphs/
^docs/training/html/
^docs/training/index.html
^docs/training/graphviz-images/
^docs/training/img/
^docs/training/output/
^docs/training/pandocfilters/