WIP: Add folder and undo operations to main menu

• Add a quickactions row to main menu containing new folder, paste and star
• Add other folder operations as menu items
• Move Undo/Redo into main menu

See the usability problems identified in #727 (closed) and #734 (closed).

What does not yet work is:

• Showing either a star or unstar button according to which action is available
• Hiding the "New Documents" menu button when action is hidden
• Staring the current folder when nothing is selected (maybe it should always star the current folder?)

I don't have an idea on what screws to turn to solve the problems. I tried using g_object_bind_property, but the staring action is not available in nautilus-toolbar.c only in nautilus-files-view.c. The same goes for the "new-document" action and the menu entry.

Would it be ok codewise to set up the properties in nautilus-files-view.c? How do I best access the toolbar from there? Something like this?:

window = gtk_widget_get_ancestor (GTK_WIDGET (view), GTK_TYPE_WINDOW);
toolbar = nautilus_window_get_toolbar(window);

Also this is based on the refactored branch, since I wanted to prevent merge conflicts.