function reference grouping

Hi! As now we have separate groups of files for every extension, we can talk again about grouping of extensions by purpose. I made some small investigations. We have <reference> for an extension. This is only allowed in <book> and <part>, so we need to make every gruop a <part> to make this work... But <part>s can only be in books, and so this would only work, if we would have the reference part as a separate <book> (this would not mean a separation from the PHP Manual, but a separation on the XML level). The other way is to go a bit deeper, and drop <reference>, as <refentry> (which we use for individual functions) can be under a <sectx> [where x is 0 < int < 6] or <section>. A <section> can contain virtually anything (we already use sections under our <partintro>s). So we can go the way to have a separate <book> for the reference part, and have the groups as <part>s, or we can drop <reference> and use <section> instead of that. Which way to go? I don't know right now, what to vote for... BUT we need to decide on this, as these are the only two methods as I can see to solve our grouping problems. Goba