* gladeui/glade-popup.c: added packing actions to glade_popup_action_populate_menu()

* gladeui/glade-widget-action.c: fixed a couple of typos in glade_widget_action_constructor()

* gladeui/glade-widget-adaptor.[ch]:

  - Added packing actions, just like properties the action tag should be inside an actions or
    packing-actions tag, also you can put an action tag inside other action tag :p

  - added GladeChildActionActivatedFunc child_action_activate to GladeWidgetAdaptorClass

  - added packing_actions list to GladeWidgetAdaptor

  - added new functions:
    glade_widget_adaptor_pack_action_add(), glade_widget_adaptor_pack_action_remove()
    and glade_widget_adaptor_child_action_activate()

* gladeui/glade-widget.[ch]:

  - added packing_actions list to GladeWidget

  - set packing actions in glade_widget_set_parent()

  - added glade_widget_get_pack_action() and glade_widget_remove_pack_action()

* gladeui/glade-xml-utils.h:

  - new tags ...