Change the process title with a cleaned-up version of the script
Document the use of setproctitle in the README
Restore SIGPIPE default action before exec(3)

Python chooses to ignore SIGPIPE, however most unix processes expect
to terminate on the signal.  Therefore failing to restore the default
action results in surprising behavior.  For example, we expect
`dd if=/dev/zero | head -c1` to return immediately.  However, prior to
this commit, that pipeline would hang forever.  Insidious forms of
data corruption or loss were also possible.

See:

  http://www.chiark.greenend.org.uk/ucgi/~cjwatson/blosxom/2009-07-02-python-sigpipe.html
  http://blog.nelhage.com/2010/02/a-very-subtle-bug/
Merge branch 'dvarrazzo/master'
Merge branch 'traviscross/master'
Replace ctime in file-stamp with mode, uid, and gid

When building on some remote filesystems (Mac NFS notably) the ctime
field may differ in the client cache and the server leading to spurious
"you modified it" warning. Tracking mode, uid and gid instead provide
most of the benefit of having ctime in the stamp without this issue.