obslog: remove now-unused code for plain styling
We now always use a non-plain formatter for the non-local-filtering
code paths, so we can remove the code for plain styling.
I couldn't figure out how to replace the fm.formatlist() by something
less about formatting, so I've only removed the irrelevant arguments
from those calls.
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/