Refactor docs

mkdocs-website/docs/en/API/application_menu.md

@@ -0,0 +1,31 @@
+### RegisterContextMenu
+
+API: `RegisterContextMenu(name string, menu *Menu)`
+
+`RegisterContextMenu()` registers a context menu with a given name. This menu
+can be used later in the application.
+
+```go
+
+    // Create a new menu
+    ctxmenu := app.NewMenu()
+
+    // Register the menu as a context menu
+    app.RegisterContextMenu("MyContextMenu", ctxmenu)
+```
+
+### SetMenu
+
+API: `SetMenu(menu *Menu)`
+
+`SetMenu()` sets the menu for the application. On Mac, this will be the global
+menu. For Windows and Linux, this will be the default menu for any new window
+created.
+
+```go
+    // Create a new menu
+    menu := app.NewMenu()
+
+    // Set the menu for the application
+    app.SetMenu(menu)
+```