migrate to dhtnet namespace

Change-Id: I7143a010bd83e8cfa7a3c8c3072ed23f6f0ba8e3
diff --git a/src/multiplexed_socket.cpp b/src/multiplexed_socket.cpp
index dd6c298..faf680e 100644
--- a/src/multiplexed_socket.cpp
+++ b/src/multiplexed_socket.cpp
@@ -51,7 +51,7 @@
     MSGPACK_DEFINE_MAP(v)
 };
 
-namespace jami {
+namespace dhtnet {
 
 using clock = std::chrono::steady_clock;
 using time_point = clock::time_point;