stablerange: add warming of the subrange
Note that this means we build standard stable subrange for all changesets in the
repository this is significantly more than what we were computing before and
result is significantly more ranges being computed.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes