checkheads: add more complexe case where a branch is split on multiple ones
We extend case A-6 and A-7 with partial counterpart. These case are interesting
because some of the partial pushing will (rightfully) works and some other won't.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes