add user manual in app instead of pdf

src/app_dialogs.cpp

@@ -5,6 +5,7 @@
 #include "node_dialog_cloud.h"
 #include "node_about.h"
 #include "node_changelog.h"
+#include "node_usermanual.h"
 
 std::shared_ptr<NodeProgressBar> App::show_progress(const std::string& title)
 {
@@ -19,6 +20,18 @@ std::shared_ptr<NodeProgressBar> App::show_progress(const std::string& title)
     return pb;
 }
 
+void App::dialog_usermanual()
+{
+    auto dialog = std::make_shared<NodeUserManual>();
+    dialog->m_manager = &layout;
+    dialog->init();
+    dialog->create();
+    dialog->loaded();
+
+    layout[main_id]->add_child(dialog);
+    layout[main_id]->update();
+}
+
 void App::dialog_changelog()
 {
     auto dialog = std::make_shared<NodeChangelog>();