OO-1068 fix wrong button group css class, compile oo theme

src/main/java/org/olat/repository/ui/author/_content/entries.html

@@ -2,7 +2,7 @@
 	<div class="o_info">$off_desc</div>
 #end
 $r.render("table")
-<div class="o_buttons_box_center clearfix">
+<div class="o_button_group clearfix">
 	#if($r.available("tools.add.owners"))
 		$r.render("tools.add.owners")
 	#end