obshistory: add the all option to obslog to show the while obs tree
Add a --all option to obslog in order to display also the successors of each
obs markers. It has the effect of showing a more comprehensive graph when a
split or a divergence happened.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes