Made upcoming concert box only show up when there are any upcoming concerts.

https://what.cd/forums.php?action=viewthread&threadid=193262

sections/artist/concerts.php

@@ -21,6 +21,8 @@
 	echo '</ul>';
 }
 $Concerts .= ob_get_clean();
+
+if isset($ArtistEvents['events']['event']) {
 ?>
 
 <div class="box">
@@ -33,6 +35,8 @@
 	</div>
 </div>
 
+<?}?>
+
 <?
 function make_concert_link($Event) {
 	// The event doesn't have a start date (this should never happen)