Refactor and modernize namespace declarations

Move all unit tests to namespace nfd::tests

Delete unused header core/algorithm.hpp

Change-Id: I5591f0c5f3bb5db67f8b45fae95471f8a555ca68
diff --git a/daemon/fw/asf-probing-module.hpp b/daemon/fw/asf-probing-module.hpp
index 654b569..0d6b212 100644
--- a/daemon/fw/asf-probing-module.hpp
+++ b/daemon/fw/asf-probing-module.hpp
@@ -28,9 +28,7 @@
 
 #include "asf-measurements.hpp"
 
-namespace nfd {
-namespace fw {
-namespace asf {
+namespace nfd::fw::asf {
 
 /** \brief ASF Probing Module
  */
@@ -97,8 +95,6 @@
   AsfMeasurements& m_measurements;
 };
 
-} // namespace asf
-} // namespace fw
-} // namespace nfd
+} // namespace nfd::fw::asf
 
 #endif // NFD_DAEMON_FW_ASF_PROBING_MODULE_HPP