Introducing a couple of real test cases.

Also, basic PIT test shows that everything works as expected...

There was one big change in PIT. Previously, when PIT entry was
satisfied, it was immediately removed. As of recently, PIT entry is
immediately removed.
diff --git a/model/ccnx-pit.h b/model/ccnx-pit.h
index 0ae3968..941b079 100644
--- a/model/ccnx-pit.h
+++ b/model/ccnx-pit.h
@@ -113,19 +113,11 @@
   virtual void
   Print (std::ostream &os) const = 0;
 
-  // template<class A,class M>
-  // void
-  // modify (A, M)
-  // {
-  //   ;
-  // }
-
-  // template<class A>
-  // void
-  // erase (A)
-  // {
-  //   ;
-  // }
+  /**
+   * @brief Get number of entries in PIT
+   */
+  virtual uint32_t
+  GetSize () const = 0;
 
   /**
    * @brief Return first element of FIB (no order guaranteed)