add a button on the main navbar for issues_pr

rainboard/templates/base.html

@@ -11,6 +11,7 @@
 {% navbar_item 'rainboard:graph' 'Graph' %}
 {% navbar_item 'rainboard:contributors' 'Contributors' %}
 {% navbar_item 'rainboard:gepetto' 'Gepetto' %}
+{% navbar_item 'rainboard:issues_pr' 'Issues / PR' %}
 {% endblock %}
 
 {% block scripts %}