function onMediaPlayerStatusChanged(status) {
        self.trigger(ReadiumSDK.Events.MEDIA_OVERLAY_STATUS_CHANGED, status);
    }
Triggers the process of opening the book and requesting resources specified in the packageData

@method openBook
@param openBookData object with open book data:

    openBookData.package: packageData, (required)
    openBookData.openPageRequest: openPageRequestData, (optional) data related to open page request
    openBookData.settings: readerSettings, (optional)
    openBookData.styles: cssStyles (optional)