face: When there are no more events to process, pausing transport instead of closing it

Change-Id: I12ad55c6ef3b6b3fce4a5b3c679eb0c6dc3cfa07
Refs: #1314
diff --git a/src/transport/tcp-transport.hpp b/src/transport/tcp-transport.hpp
index b97e2a1..6795580 100644
--- a/src/transport/tcp-transport.hpp
+++ b/src/transport/tcp-transport.hpp
@@ -33,6 +33,12 @@
   virtual void 
   close();
 
+  virtual void
+  pause();
+
+  virtual void
+  resume();
+
   virtual void 
   send(const Block& wire);