fw+doc: Renaming and extending limit extenstion

SimpleLimits now called PerOutFaceLimits.  Also, there is now
PerFibLimits that is inherited from PerOutFaceLimits and implements
additional check.

Also, this commit includes a couple of tricks to improve documentation
of templated classes (PerOutFaceLimits and PerFibLimits). Not ideal, but
much better than before.
diff --git a/model/fw/ndn-forwarding-strategy.cc b/model/fw/ndn-forwarding-strategy.cc
index 14db750..770613b 100644
--- a/model/fw/ndn-forwarding-strategy.cc
+++ b/model/fw/ndn-forwarding-strategy.cc
@@ -44,13 +44,19 @@
 #include <boost/tuple/tuple.hpp>
 namespace ll = boost::lambda;
 
-NS_LOG_COMPONENT_DEFINE ("ndn.ForwardingStrategy");
-
 namespace ns3 {
 namespace ndn {
 
 NS_OBJECT_ENSURE_REGISTERED (ForwardingStrategy);
 
+NS_LOG_COMPONENT_DEFINE (ForwardingStrategy::GetLogName ().c_str ());
+
+std::string
+ForwardingStrategy::GetLogName ()
+{
+  return "ndn.fw";
+}
+
 TypeId ForwardingStrategy::GetTypeId (void)
 {
   static TypeId tid = TypeId ("ns3::ndn::ForwardingStrategy")