Add application settings file: settings.json

```
In settings file we could have options for customizing application's window, 
some of the options might allow setting:
 * default window size
 * minimum/maximum window size when resizing
 * disable maximize button
 * center the window on the screen
```

Original issue reported on code.google.com by `czarek.t...@gmail.com` on 13 Jan 2013 at 1:19
