checkheads: import our own copy of the checkheads code I expect enough change and experimental will be made that is it worthwhile having them done in evolution close to the rest of the exchange tests make sense.

syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes