[libvirt] Updated application development guide on libvirt.org

[David Jorm]

I have published an updated draft of the application development guide at:

http://libvirt.org/guide/

It includes expanded content, editing and formatting for:

* Chapter 3 - Connections
* Chapter 4 - Guest Domains
* Chapter 7 - Network Interfaces

Additional content for Chapter 3 has been provided to me, and will be included soon.

Thanks
David