[CentOS] CentOS 6 and pxeboot

>Ok, now you have me confused: should there not be such image files?

Look at the file names, it should be intuitive. As per the docs, if they exist,
updates.img will apply updates:) etc...

http://www.arrfab.net/blog/?p=305

Looks like it's been removed from the 6x docs, but I haven't the time to be thorough
atm but I see it in <=5x docs.

A patch for anaconda related to nfs installs shows its certainly in, and the apache
logs indicate anaconda's attempt to find it...