core: copy Animations from SettingsObjectWrapper to qPref as its own class

Update set/get functions to follow common name scheme:
- get function have same name as in struct preferences
- set function have set_<name in struct preferences>
- signal function have <name in struct preferences>_changed

one class one .h/.cpp is the C++ idiom. Having load/sync of each
variable in 1 functions (in contrast to the distributed way SettingsObjectWrapper
handles it) secures the same storage name is used. Having the set/get/load/sync
functions grouped together makes it easier to get an overview.

REMARK: this commit only defines the class, it is not active in production
Signed-off-by: Jan Iversen <jani@apache.org>

core/settings/qPref.h

@@ -6,6 +6,7 @@
 #include <QSettings>
 #include "core/pref.h"
 
+#include "qPrefAnimations.h"
 #include "qPrefDisplay.h"
 
 class qPref : public QObject {
@@ -34,8 +35,6 @@ public:
 
 	const QString canonical_version() const;
 	const QString mobile_version() const;
-
-private:
 };
 
 #endif