[development] Move all core modules into their own directories.

[Kobus Myburgh]

> One of the "problems" I was hoping to solve with the metadata files 
> being PHP is we have a chance to move the entire _help hook there,
which 
> will make the .module file smaller, will give the doc team their own

> little "namespace" to worry about, and will lessen the load of the 
> .module file in memory (since we're not loading all the help text in,

> especially when, for a visitor it rarely, if ever, gets parsed).

While I understand your point here too, Morbus, I do feel that the
contents of the _help() hook is abysmally little in most contrib
modules, except the ones that the author took real pride in making, such
as eCommerce, Views and a few others. Some modules were written to
scratch an itch and stayed that way for several versions of Drupal,
mostly just porting it to the new version (if at all) and weren't
actively developed. Such modules often have less-than-sufficient help
information, so my question is this: "How much space will this save in
.module files?"

Of course this point I make above is only for contrib, not for Core. If
a module can be 3K smaller on average for Core and 500 bytes smaller on
average for contrib modules, just how much would this increase
performance?

Kobus