Move stackview example to manual tests folder

Change-Id: I5d9b39531a866d7fc5765332d364e6e2793b5b13
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>

examples/quick/controls/controls.pro

@@ -3,7 +3,6 @@ TEMPLATE = subdirs
 SUBDIRS += \
     gallery \
     splitview \
-    stackview \
     tableview \
     touch \
     basiclayouts

examples/quick/controls/stackview/stackview.pro

-TEMPLATE = aux
-
-OTHER_FILES += \
-    main.qml \
-    ButtonMenu.qml \
-    View.qml

src/controls/doc/src/qtquickcontrols-examples.qdoc

@@ -81,18 +81,6 @@
     desktop application using \l{Qt Quick Controls}.
 */
 
-/*!
-    \example stackview
-    \title Qt Quick Controls - Stack View Example
-    \ingroup qtquickcontrols_examples
-    \brief An example for a stack-based navigation model.
-    \image qtquickcontrols-example-stackview.png
-
-    This example shows how to implement a stack-based navigation model
-    in a Qt Quick application using a \l{StackView} component from
-    \l{Qt Quick Controls}.
-*/
-
 /*!
     \example tableview
     \title Qt Quick Controls - Table View Example