[gtk+] Drop no-longer-used migration docs

[Matthias Clasen <matthiasc src gnome org>]

commit 83f5e4868c7322ddcbb831dd72744da887e8d17f
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jan 2 23:57:03 2011 -0500

    Drop no-longer-used migration docs

 .../reference/gtk/migrating-ClientSideWindows.sgml |   64 ---
 docs/reference/gtk/migrating-GtkAboutDialog.sgml   |   98 -----
 docs/reference/gtk/migrating-GtkAction.sgml        |  445 --------------------
 docs/reference/gtk/migrating-GtkAssistant.sgml     |  178 --------
 docs/reference/gtk/migrating-GtkBuilder.sgml       |  102 -----
 docs/reference/gtk/migrating-GtkColorButton.sgml   |   54 ---
 docs/reference/gtk/migrating-GtkComboBox.sgml      |  213 ----------
 docs/reference/gtk/migrating-GtkEntry-icons.sgml   |  141 ------
 docs/reference/gtk/migrating-GtkFileChooser.sgml   |  163 -------
 docs/reference/gtk/migrating-GtkIconView.sgml      |  153 -------
 docs/reference/gtk/migrating-GtkLabel-links.sgml   |   24 -
 docs/reference/gtk/migrating-GtkLinkButton.sgml    |   81 ----
 docs/reference/gtk/migrating-GtkRecentChooser.sgml |  323 --------------
 docs/reference/gtk/migrating-GtkTooltip.sgml       |   66 ---
 14 files changed, 0 insertions(+), 2105 deletions(-)