Update on the goal page

Some things to note in this patch:
   - we do extend libvirt scope beyond purely managing domains, there is
     already a number of blocks which are here as helpr functions to
     manage the resources on the host.
   - we are expanding in the direction of libvirt being sufficient to do
     most of the management on the Host (but within the limits of the need
     for virtualization, e.g. managing users on the host is out of scope)
   - we don't require anymore APIs to be supported by multiple
     hypervisors to get in, it's already the case in practice, but we
     should still make sure the semantic of those APIs are clear. We
     added quite a bit for QEmu, but for example I saw on IRC that VBox
     could emulate a network unplug/replug on a domain interface, and
     that would be a good addition even if a priori no other hypervisor
     supports it.
   - Make clear that all libvirt APIs are available remotely, which is
     key to use libvirt for building management tools.
   - link the goal page from the project main page

As for libvirt project directions, I think it just reflects the natural
evolution in the last couple of years. We are less hypervisor agnostic
and extending in the Host management. Clearly there is interest in
making sure libvirt is complete in term of features for the hypervisors
supported, especially the ones like KVM or LXC which don't really have
integrated management library.

* docs/goals.html.in: update the goals page
* docs/index.html.in: link it from the top page

docs/goals.html.in

@@ -16,20 +16,35 @@
     <p class="image">
       <img alt="Hypervisor and domains running on a node" src="node.gif"/>
     </p>
-    <p>Now we can define the goal of libvirt: to provide a common generic
-    and stable layer to securely manage domains on a node. The node may be
-    distant and libvirt should provide all APIs needed to provision, create,
-    modify, monitor, control, migrate and stop the domains, within the limits
-    of the support of the hypervisor for those operations. Multiple nodes may
-    be accessed with libvirt simultaneously but the APIs are limited to
-    single node operations.</p>
+    <p>Now we can define the goal of libvirt: <b> to provide a common and
+    stable layer sufficient to securely manage domains on a node, possibly
+    remote</b>.</p>
+    <p> As a result, libvirt should provide all APIs needed to do the
+    management, such as: provision, create, modify, monitor, control, migrate
+    and stop the domains - within the limits of the support of the hypervisor
+    for those operations.
+    Not all hypervisors provide the same operations; but if an operation is
+    useful for domain management of even one specific hypervisor it is worth
+    providing in libvirt.
+    Multiple nodes
+    may be accessed with libvirt simultaneously, but the APIs are limited to
+    single node operations. Node resource operations which are needed
+    for the management and provisioning of domains are also in the scope of
+    the libvirt API, such as interface setup, firewall rules, storage management
+    and general provisioning APIs. Libvirt will also provide the state
+    monitoring APIs needed to implement management policies, obviously
+    checking domain state but also exposing local node resource consumption.
+    </p>
     <p>This implies the following sub-goals:</p>
     <ul>
-      <li>the API should not be targeted to a single virtualization environment
-    which also means that some very specific capabilities which are not generic
-    enough may not be provided as libvirt APIs</li>
+      <li>All API can be carried remotely though secure APIs</li>
+      <li>While most API will be generic in term of hypervisor or Host OS,
+    some API may be targeted to a single virtualization environment
+    as long as the semantic for the operations from a domain management
+    perspective is clear</li>
       <li>the API should allow to do efficiently and cleanly all the operations
-    needed to manage domains on a node</li>
+    needed to manage domains on a node, including resource provisioning and
+    setup</li>
       <li>the API will not try to provide high level virtualization policies or
     multi-nodes management features like load balancing, but the API should be
     sufficient so they can be implemented on top of libvirt</li>

docs/index.html.in

@@ -8,7 +8,8 @@
     <ul>
       <li>
         A toolkit to interact with the virtualization capabilities
-        of recent versions of Linux (and other OSes).
+        of recent versions of Linux (and other OSes), see our
+        <a href="goals.html">project goals</a> for details.
       </li>
       <li>
         Free software available under the