DOC: mention Anaconda; clean some old junk out of the FAQ

This changeset is only a start on fixing the installation section of the FAQ.  At the very least, another changeset is needed to make the OSX binary package installation section match whatever we will be doing for 1.4.  (Wheels this time?) I suspect much more is needed--ideally a complete re-write, but if nothing else, note the move from easy_install to pip.