Utils: Introduce a TemporaryDirectory and TemporaryFile class

Both wrap the corresponding Qt class, but make sure all temporary files
or directories are created inside a "master temporary directory".

Change-Id: I55461be507c828c965224c02863ea5ed9bbf9498
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/ios/iosdeploystep.cpp

@@ -42,8 +42,9 @@
 
 #include <qtsupport/qtkitinformation.h>
 
+#include <utils/temporaryfile.h>
+
 #include <QDir>
-#include <QTemporaryFile>
 #include <QFile>
 #include <QSettings>
 
@@ -275,7 +276,7 @@ void IosDeployStep::checkProvisioningProfile()
         return;
     end += 8;
 
-    QTemporaryFile f;
+    Utils::TemporaryFile f("iosdeploy");
     if (!f.open())
         return;
     f.write(provisionData.mid(start, end - start));