[libvirt] [Docs] More work on the API and architecture

Another patch, incomplete adding a new page api.html[.in] with the goals of describing the main API concepts, architectures, naming conventions, etc ... It includes Dan's graphics and a change of how the stylesheet process the .html.in content allowing to turn <code class='docref'>foo</code> into a link to reference for foo in the API page. Ultimately I should be able to load the API description from the stylesheet and do that link generation automagically without any markup (like all the links in the API reference). Still need to write the drivers and remote sections, and augment some of the APIs entry points, but it's a first step and better in than out. Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel(a)veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/