shill: Remove the "resource" superclass

The "resource" superclass was meant at some point to be some
sort of crude mockup of a possible refcounting scheme.  Drop
this idea, and use base/ref_counted for Devices which will
likely need multiple entities referencing it.

BUG=chromium-os:12933
TEST=Rebuild

Change-Id: Id267049e881037422271f1611dcc8a5e90e9abac
Reviewed-on: http://gerrit.chromium.org/gerrit/723
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
diff --git a/manager.h b/manager.h
index 9847705..309c1db 100644
--- a/manager.h
+++ b/manager.h
@@ -8,7 +8,6 @@
 #include <vector>
 #include <base/scoped_ptr.h>
 
-#include "shill/resource.h"
 #include "shill/shill_event.h"
 #include "shill/service.h"
 #include "shill/device.h"
@@ -16,7 +15,7 @@
 
 namespace shill {
 
-class Manager : public Resource {
+class Manager {
  public:
   // A constructor for the Manager object
   explicit Manager(ControlInterface *control_interface,