Add template method for rendering row grid component

so custom event hooks can be added more easily, when needed

tailbone/templates/master/view.mako

@@ -107,13 +107,17 @@
           % if rows_title:
               <h4 class="block is-size-4">${rows_title}</h4>
           % endif
-          <tailbone-grid ref="rowGrid" id="rowGrid"></tailbone-grid>
+          ${self.render_row_grid_component()}
       % else:
           ${rows_grid|n}
       % endif
   % endif
 </%def>
 
+<%def name="render_row_grid_component()">
+  <tailbone-grid ref="rowGrid" id="rowGrid"></tailbone-grid>
+</%def>
+
 <%def name="render_this_page_template()">
   % if master.has_rows:
       ## TODO: stop using |n filter