Boolean options can not be True globally but False locally

[Philippe Mathieu]

The following syntax prevents the showNavigation to be set to True globally but False locally as True always wins:

  var showNavigation = o.showNavigation || this.settings.showNavigation;

In my opinion the local option should win if it is defined, thus the following change:

  var showNavigation = typeof o.showNavigation !== 'undefined' ?
                       o.showNavigation :
                       this.settings.showNavigation;

Other Boolean options are similarly affected (e.g. showCloseBox).

[Ryu | Chia-Lung Chen]

nice catch @71FIL, I noticed that somewhere too, can you help this part ? that would be a good first bug i think :)