eo-agenda-widget code editing

First of all I want to thank all people who was involved by creating this amazing plugin!
Im using it since two years now and its getting better and better.

I have just one tiny problem with eo-agenda-widget. As you can see on this screenshot, there is no specific date for all the games to see. Instead of “All day (German: ganztags)” it should display a concrete date like Fr, 17.03
http://fs5.directupload.net/images/160211/liiyijm8.jpg

Ive also found the specific code to change (event-organiser/classes/class-eo-agenda-widget.php), but I don’t know how. I already tried to replace ‘All day’ with different words like ‘date’; ‘dates’; ‘D, d.m’; ‘eventdate’ but nothing worked.

It would be great if someone could help me.

<span><strong>
	<% if( event.all_day ){ %><?php esc_html_e( 'All day', 'eventorganiser' ); ?><% }
        else{ %><%= event.start.format(this.param.item_format) %><% } %>
</strong></span>

https://wordpress.org/plugins/event-organiser/