Bump MODULE_VERSION to 5.1.2

Change-Id: I6f3686ed8b527004af33f4ef62bf835220f5a7a9
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>

.qmake.conf

 load(qt_build_config)
 CONFIG += qt_example_installs
 
-MODULE_VERSION = 5.1.1
+MODULE_VERSION = 5.1.2