apps: Fixing ability to change q and s attributes in ndn::ConsumerZipfMandelbrot

Signed-off-by: Alexander Afanasyev <alexander.afanasyev@ucla.edu>

closes #18
diff --git a/apps/ndn-consumer-zipf-mandelbrot.h b/apps/ndn-consumer-zipf-mandelbrot.h
index 71113b2..b9f4d17 100644
--- a/apps/ndn-consumer-zipf-mandelbrot.h
+++ b/apps/ndn-consumer-zipf-mandelbrot.h
@@ -70,7 +70,19 @@
 
   uint32_t
   GetNumberOfContents () const;
-  
+
+  void
+  SetQ (double q);
+
+  double
+  GetQ () const;
+
+  void
+  SetS (double s);
+
+  double
+  GetS () const;
+
 private:
   uint32_t m_N;  //number of the contents
   double m_q;  //q in (k+q)^s