DiscoveryClient stops resusbcribing even after ttl period.

On no response from discovery server and no error, subscribe timer is not restarted as
the subscribe_cb_called_ flag was not reset.  Setting the flag appropriately on every
subscribe request, so subscribe timer can be restarted during the case above.

Remove unnecessary curl timeout traces, use stats counters.

Change-Id: Ief95c50ee91c47f8d12f6390d28c8cabca8c5ffd
Closes-Bug:1563002

src/discovery/client/discovery_client.cc

@@ -489,6 +489,8 @@ void DiscoveryServiceClient::ReEvaluatePublish(std::string serviceName,
             resp->publish_msg_ = ss.str();
         }
 
+        resp->pub_sent_++;
+        resp->publish_cb_called_ = false;
         /* Send publish unconditionally */
         DISCOVERY_CLIENT_TRACE(DiscoveryClientMsg, resp->publish_hdr_,
                                serviceName, resp->publish_msg_);
@@ -564,6 +566,7 @@ void DiscoveryServiceClient::Publish(std::string serviceName) {
 
         DSPublishResponse *resp = loc->second;
         resp->pub_sent_++; 
+        resp->publish_cb_called_ = false;
         SendHttpPostMessage(resp->publish_hdr_, serviceName, resp->publish_msg_);
 
         DISCOVERY_CLIENT_TRACE(DiscoveryClientMsg, resp->publish_hdr_, 
@@ -661,6 +664,7 @@ void DiscoveryServiceClient::Subscribe(std::string serviceName, uint8_t numbOfIn
         DSResponseHeader *resp = loc->second;
         resp->subscribe_timer_->Cancel();
         resp->sub_sent_++;
+        resp->subscribe_cb_called_ = false;
         SendHttpPostMessage("subscribe", serviceName, resp->subscribe_msg_);
     }
 }
@@ -888,6 +892,7 @@ void DiscoveryServiceClient::SendHeartBeat(std::string serviceName,
                                     std::string msg) {
     DSPublishResponse *resp = GetPublishResponse(serviceName); 
     resp->pub_hb_sent_++;
+    resp->heartbeat_cb_called_ = false;
     SendHttpPostMessage("heartbeat", serviceName, msg);
 }