[atk] doc: add an overview

[Alejandro Piñeiro Iglesias <apinheiro src gnome org>]

commit fdf5f9c1cb5af00fd9a85534bc1460fa3d2869e1
Author: Alejandro Piñeiro <apinheiro igalia com>
Date:   Tue Feb 18 18:29:29 2014 +0100

    doc: add an overview
    
    This is the same overview used for ATK releases. In any case
    this should be improved and updated.

 docs/atk-docs.sgml |   20 +++++++++++++++++++-
 1 files changed, 19 insertions(+), 1 deletions(-)
---
diff --git a/docs/atk-docs.sgml b/docs/atk-docs.sgml
index dfe315a..9f9c736 100644
--- a/docs/atk-docs.sgml
+++ b/docs/atk-docs.sgml
@@ -42,7 +42,25 @@
 
   <chapter id="overview">
     <title>Overview</title>
-    Atk is cool
+     <para>
+       GNOME provides support for accessibility devices using the ATK
+       framework. This framework defines a set of interfaces to which
+       graphical interface components adhere. This allows, for instance,
+       screen readers to read the text of an interface and interact with its
+       controls. ATK support is built into GTK+ and the rest of the GNOME
+       platform, so any application using GTK+ will have reasonable
+       accessibility support for free.
+     </para>
+
+     <para>
+     Nonetheless, you should be aware of accessibility issues when when
+     developing your applications. Although GTK+ interfaces provide
+     reasonable accessibility by default, you can often improve how well
+     your program behaves with accessibility tools by providing additional
+     information to ATK. If you develop custom widgets, you should ensure
+     that they expose their properties to ATK
+     </para>
+
   </chapter>
 
   <chapter id="atkobject">