model: Another set of refactoring/renaming to make code compile (not tested yet)

Refs #1005 (http://redmine.named-data.net/)
diff --git a/model/ndn-content-object.cc b/model/ndn-content-object.cc
index d287ca7..7fcb459 100644
--- a/model/ndn-content-object.cc
+++ b/model/ndn-content-object.cc
@@ -30,20 +30,19 @@
 namespace ns3 {
 namespace ndn {
 
-NS_OBJECT_ENSURE_REGISTERED (ContentObject);
-NS_OBJECT_ENSURE_REGISTERED (ContentObjectTail);
-
-ContentObject::ContentObject ()
+ContentObject::ContentObject (Ptr<Packet> payload/* = Create<Packet> ()*/)
   : m_signature (0)
+  , m_payload (payload)
+  , m_wire (0)
 {
 }
 
 ContentObject::ContentObject (const ContentObject &other)
   : m_name (Create<Name> (other.GetName ()))
-  , m_freshness (other->GetFreshness ())
-  , m_timestamp (other->GetTimestamp ())
-  , m_signature (other->GetSignature ())
-  , m_payload (other->GetPayload ()->Copy ())
+  , m_freshness (other.GetFreshness ())
+  , m_timestamp (other.GetTimestamp ())
+  , m_signature (other.GetSignature ())
+  , m_payload (other.GetPayload ()->Copy ())
   , m_wire (0)
 {
 }
@@ -117,5 +116,17 @@
   // os << "<ContentObject><Name>" << GetName () << "</Name><Content>";
 }
 
+void
+ContentObject::SetPayload (Ptr<Packet> payload)
+{
+  m_payload = payload;
+}
+
+Ptr<const Packet>
+ContentObject::GetPayload () const
+{
+  return m_payload;
+}
+
 } // namespace ndn
 } // namespace ns3