[glade] (34 commits) ...Add UI interactive introduction

[Juan Pablo Ugarte <jpu src gnome org>]

Summary of changes:

  6ba2785... GladeWindow: remove dock system (*)
  1c870ed... GladeWindow: remove palette related actions from view menu (*)
  1d85dd0... GladeWindow: remove palette (*)
  3fba517... GladeWindow: move inspector to palette place. (*)
  833f799... GladeWindow: remove unused right_paned. (*)
  995eeb1... GladeAdaptorChooser: add GLADE_ADAPTOR_CHOOSER_SKIP_DEPRECA (*)
  87d78ab... GladeDesignView: include all widget in widget chooser (*)
  3513a72... GladeAdaptorChooser: set viewport max content height instea (*)
  366d64a... GladeWindow: moved statusbar on top of workspace (*)
  4d9bc5f... GladeEditor: add show-border property (*)
  0656444... GladeWindow: replace menubar with headerbar (*)
  b0ffaab... GladeWindow: remove unused view actions (*)
  c733593... GladeWindow: replace main notebook with stack (*)
  f4cd341... GladeCloseButton: removed unused class (*)
  140b355... GladeWidgetAdaptor: do not query user by default (*)
  fee15da... _GladeAdaptorChooser: add new API (*)
  02afd23... Rename GladeAdaptorChooser to GladeAdaptorChooserWidget (*)
  8ad93ee... GladeAdaptorChooser: implemented new class to replace palet (*)
  e3b1fb4... GladeUI plugin: add support for GladeAdaptorChooser (*)
  57822f5... GladeWindow: add GladeAdaptorChooser (*)
  e438770... GladePlaceholder: use middle click button to create more th (*)
  b5ec733... Gtk+ catalog: split control and display widget groups (*)
  4e55a66... GladeAdaptorChooserWidget: add show-group-title property (*)
  58fe151... GladeAdaptorChooser: show group title in chooser with more  (*)
  d59478d... GladeDesignView,GladePlaceholder: use gtk_popover_popup() i (*)
  5c5cec9... GladeAdaptorChooserWidget: set scrolled window max height o (*)
  65036a6... GladeWindow: moved css to glade-window.css file (*)
  e0f591f... Do not open a new project by default (*)
  2cf6a47... Added glade-brand-symbolic icon (*)
  4bb5aac... GladeWindow: add main stack with logo (*)
  5057982... GladeWindow: remove unused project list (*)
  9107284... GladeWindow: move all project actions to headerbar (*)
  97be4a2... GladeWindow: port to GAction (*)
  dc40fc5... Add UI interactive introduction (*)

(*) This commit already existed in another branch; no separate mail sent