Squish: Move wizard into plugin

Avoids a soft assert when parsing the wizards without having
the Squish plugin enabled.
As the Squish wizard is using customized wizard generators
that are only available if Squish is loaded we should limit
the presence of the wizard file to this case.

Change-Id: I091c1e429f28b07679245abdc9a638135af84761
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/squish/squish.qrc

@@ -8,5 +8,6 @@
         <file>images/jumpTo@2x.png</file>
         <file>images/data.png</file>
         <file>images/data@2x.png</file>
+        <file>wizard/wizard.json</file>
     </qresource>
 </RCC>

src/plugins/squish/squishplugin.cpp

@@ -105,6 +105,7 @@ void SquishPluginPrivate::initializeMenuEntries()
 bool SquishPlugin::initialize(const QStringList &, QString *)
 {
     dd = new SquishPluginPrivate;
+    ProjectExplorer::JsonWizardFactory::addWizardPath(":/squish/wizard/");
     return true;
 }