Adding hooks to configuration page

[Wesley Shields]

I'm attaching a patch which adds hooks to the configuration page. The
patch lists all of the hooks, and leaves the unused ones with an empty
command. I find this to be useful so I don't have to go look up what the
names of any unused hooks are.

A screenshot of what it looks like is available at [1].

This is the first time I've actually looked at the PHP code so I would
appreciate another pair of eyes on it.

[1]: http://atarininja.org/~wxs/images/hooks.png

-- WXS