Update doc/faq/johns_bsd_pitch.rst

add some fixes from http://mail.scipy.org/pipermail/scipy-user/2007-January/010602.html
Merge pull request #261 from endolith/patch-1

Update doc/faq/johns_bsd_pitch.rst

add some fixes from the version at http://mail.scipy.org/pipermail/scipy-user/2007-January/010602.html