Problem statement
=================
On-disk registry for mapping namespace to typelib. 
Conceptually similar to mono /etc/mono/config.

It should be possible in a dynamic language such as python to just do:

>>> import PythonIntrospectionBindings
>>> import Gtk


Gtk should be a special namespace provided by the package containing the
Gtk namespace

Layout of the on disk tool
==========================

Location to should be /var/lib/glib/introspection-registry.xml
Should be read completely. Not expected to be larger than one page on most
systems.

Layout in XML:

<root>
  <registry-path location="/usr/lib/typelibs/1.0/">
  <registry-path location="$HOME/.typelibs/">
  <entry namespace="Gtk" 
         library-location="libgtk-x11-2.0.so.0"
         typelib-location="gtk.typelib"/>
</root>

FIXME: version?
FIXME: pkg-config name?

The overhead should be reduced to a minimum, both runtime and memory footprint.
Thus a binary format that is mmap(2):able is ideal:

gir-registry-tool
================
Is a command line utility, probably written in C which should be used
to update/modify the registry.

Example use cases, installing a new typelib

gir-registry-tool --install Gtk /usr/lib/glib/introspection/gtk.typelib 2.12.0
gir-registry-tool --uninstall Gtk /usr/lib/glib/introspection/gtk.typelib 2.12.0

It's the registry tools responsibility to sort the disk format.

API
===

libgirepository should provide an api:

gi_locale_typelib (const gchar *name, const gchar * version);

version should NULL, if so it should pick the first one in the on-disk registry.

libgirepository should mmap the registry and read it when that API is called
the first time.