Implementing base support for TCP-style window-based limiting on per-FIB-prefix and per-face granularity

Currently, limits are supported only by ndn::fw::Limits forwarding
strategy and only at the very basic (not fully tested) level.
diff --git a/helper/ndn-stack-helper.cc b/helper/ndn-stack-helper.cc
index 9fcc8f2..d84b86b 100644
--- a/helper/ndn-stack-helper.cc
+++ b/helper/ndn-stack-helper.cc
@@ -270,6 +270,8 @@
               NS_LOG_INFO ("Max packets per second: " << maxInterestPackets);
               NS_LOG_INFO ("Max burst: " << m_avgRtt.ToDouble (Time::S) * maxInterestPackets);
 
+              // Set max to BDP
+              face->GetLimits ()->SetMaxLimit (m_avgRtt.ToDouble (Time::S) * maxInterestPackets);
             }
         }