Improve error message on plugging loading failure

src/utils/PluginsLoader.cpp

 #include <utils/PluginsLoader.hpp>
 
 #include <utils/ConsoleManager.hpp>
+#include <utils/Demangle.hpp>
 
 #include <dlfcn.h>
 
@@ -40,7 +41,7 @@ PluginsLoader::_open(const std::string& plugin)
   } else {
     std::cerr << " *" << rang::fgB::red << "cannot load " << rang::fg::reset << '\"' << rang::fgB::yellow << plugin
               << rang::fg::reset << "\"\n";
-    std::cerr << "   " << rang::fgB::magenta << dlerror() << rang::fg::reset << '\n';
+    std::cerr << "   " << rang::fgB::magenta << demangle(dlerror()) << rang::fg::reset << '\n';
   }
 }