migrate to dhtnet namespace

Change-Id: I7143a010bd83e8cfa7a3c8c3072ed23f6f0ba8e3
diff --git a/include/upnp/upnp_thread_util.h b/include/upnp/upnp_thread_util.h
index 6bc5271..564a6eb 100644
--- a/include/upnp/upnp_thread_util.h
+++ b/include/upnp/upnp_thread_util.h
@@ -13,7 +13,7 @@
         /*JAMI_ERR() << "The calling thread " << getCurrentThread() \
                    << " is not the expected thread: " << threadId_;*/
 
-namespace jami {
+namespace dhtnet {
 namespace upnp {
 
 class UpnpThreadUtil