TargetSetupPage: Generalize the page

Generalize the target setup page and move it into projectexplorer

Move the qmake specific code into a projectimporter class with
a specialization for qmake projects in the qt4projectmanager.

This change depends heavily on the BuildConfigurationFactory cleanups
done earlier and completes that change in such a way that generic
build configuration factories are now in theory possible. The
remaining problem is how to select the best factory of several that
claim to be able to handle a kit and that is left for the next patch.

Change-Id: I47134cb1938c52adebcdc1ddfe8dbf26abbbbeee
Reviewed-by: Daniel Teske <daniel.teske@digia.com>

src/plugins/qt4projectmanager/qt4projectmanagerplugin.cpp

@@ -53,7 +53,6 @@
 #include "qt-desktop/desktopqtversionfactory.h"
 #include "qt-desktop/simulatorqtversionfactory.h"
 #include "winceqtversionfactory.h"
-#include "unconfiguredprojectpanel.h"
 #include "qmakekitinformation.h"
 #include "profilehighlighterfactory.h"
 
@@ -156,7 +155,6 @@ bool Qt4ProjectManagerPlugin::initialize(const QStringList &arguments, QString *
 
     addAutoReleasedObject(new ProFileCompletionAssistProvider);
     addAutoReleasedObject(new ProFileHoverHandler(this));
-    addAutoReleasedObject(new UnconfiguredProjectPanel);
     addAutoReleasedObject(new ProFileHighlighterFactory);
 
     //menus