New tool for better understanding the codebase, to complement the wiki.

Hi,

I was bored while waiting for LibO to compile, and I was taking a look
at the wiki docs for development. I found a page "Code Overview", but
it looks really out of date.
(http://wiki.documentfoundation.org/Development/Code_Overview). Then I
thought maybe I should update it, and then I thought it would be
better to do it using software.

I cloned the tdf/misc repo on github,
(https://github.com/TheJosh/tdf-misc), and committed a tool into
there, "module_readmes".

It uses cgit to download the README or readme.txt files in all of the
top-level directories, and it generates some HTML files for easy
viewing. The first paragraph (everything before an empty line) is
considered the "short description", and is shown on the list page.
Clicking on a module shows the full description, as well as a link to
the tree in cgit.

You can see the result here:
http://thejosh.info/libreoffice/module_readmes/

Now of course all we need is to add more README files.

Cheers,
Josh