1. Add jQuery to your jekyll blog if its not there yet. I am adding it to _includes/head.html
<script src="//code.jquery.com/jquery-1.11.3.min.js"></script>
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
  1. Create additional include where we will make our magick. I did this in _includes/google__analytics.html.
$(document).ready(function(){
	$('.ga-link').on('click', function(){
		if (typeof(ga)!=="undefined"){
			ga('send',{
				hitType: 'event',
				eventCategory: 'click',
				eventAction: 'outbound',
				eventLabel: $(this).attr('href')
			});	  		
	  	}
	});
)};	

File with this code is included in default.html

{% include google_analytics.html %} 
  1. Add class=’ga-link’ to all links you want to track to google analytics.
<a href="https://github.com/timoshenkoav" class='ga-link' target='_blank'>

I`ve created such include to help generate links tracked:

<a href="" class="ga-link" target='_blank'></a>

Now if i want to have such link i can use:

{% include ga_link.html 
	title="GitHub" 
	url="https://github.com" 
%}