Use --show-preamble value to display (of not) plugin load info

src/utils/PluginsLoader.cpp

 #include <utils/PluginsLoader.hpp>
 
+#include <utils/ConsoleManager.hpp>
+
 #include <dlfcn.h>
 
 #include <rang.hpp>
@@ -32,9 +34,11 @@ PluginsLoader::_open(const std::string& plugin)
   auto handle = dlopen(plugin.c_str(), RTLD_NOW);
   if (handle != nullptr) {
     m_dl_handler_stack.push(handle);
+    if (ConsoleManager::showPreamble()) {
       std::cout << " * \"" << rang::fgB::green << plugin << rang::fg::reset << "\"\n";
+    }
   } else {
-    std::cout << "   " << rang::fgB::red << "cannot load " << rang::fg::reset << '\"' << rang::fgB::yellow << plugin
+    std::cerr << "   " << rang::fgB::red << "cannot load " << rang::fg::reset << '\"' << rang::fgB::yellow << plugin
               << rang::fg::reset << "\"\n";
   }
 }
@@ -58,7 +62,7 @@ PluginsLoader::PluginsLoader()
       std::vector<std::string> path_vector = split(paths);
       for (auto&& path : path_vector) {
         if (access(path.c_str(), R_OK) == -1) {
-          std::cout << ' ' << rang::fgB::red << 'X' << rang::fg::reset << " cannot access plugin dir \""
+          std::cerr << ' ' << rang::fgB::red << 'X' << rang::fg::reset << " cannot access plugin dir \""
                     << rang::fgB::yellow << path << rang::fg::reset << "\"\n";
         } else {
           for (auto&& entry :
@@ -79,13 +83,17 @@ PluginsLoader::PluginsLoader()
   plugin_vector.resize(std::distance(plugin_vector.begin(), std::unique(plugin_vector.begin(), plugin_vector.end())));
 
   if (plugin_vector.size() > 0) {
+    if (ConsoleManager::showPreamble()) {
       std::cout << rang::style::bold << "Loading plugins" << rang::style::reset << '\n';
+    }
     for (auto&& plugin : plugin_vector) {
       this->_open(plugin);
     }
+    if (ConsoleManager::showPreamble()) {
       std::cout << "-------------------------------------------------------\n";
     }
   }
+}
 
 PluginsLoader::~PluginsLoader()
 {