Don't Close TCP Connection/Server on destruction.

If the connection is open when the destructor is called it's a bug! Don't
want to try to compensate for bugs.

src/net.cc

@@ -117,7 +117,6 @@ Connection::~Connection ()
 {
   assert(stream_.recvfd < 0 && "garbage collecting open Connection"); 
   assert(stream_.sendfd < 0 && "garbage collecting open Connection"); 
-  ForceClose();
 }
 
 Handle<Value>

src/net.h

@@ -139,7 +139,7 @@ protected:
   }
 
   virtual ~Server () {
-    evcom_server_close (&server_); 
+    assert(server_.fd >= 0);
   }
 
   int Listen (struct sockaddr *address, int backlog) {