touch: shorten touch's docstring to make it fit into a one line
This make it show completely (untruncated) in `hg help -e evolve`.
This follows up on fed946edc293 where the docstring got unwrap for that
purpose and thus made the line length exceed 80 columns.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
^tests/.*\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes