Add OK/Cancel buttons and DialogTitle locales

I have created a DialogToggleButton (for doing a file manager for my own cms) but I can't define locales for OK/Cancel dialog buttons and dialog title. 

So I add some options for `DialogButton` : `dialogOkButton`, `dialogCancelButton` and `dialogTitle`.

To use it : 
```
Raptor.registerUi(new Raptor.DialogToggleButton({
    name: 'someButton',
    title: 'SomeTitle',
    dialogOkButton: 'OK',
    dialogCancelButton: 'Cancel',
    dialogTitle: 'A dialog title',
    // ...
});
```

It's a sort of workaround, because I can't find how to access locales in Raptor.