Move/rename 2k15 to next

The name has been changed to protect the innocent. (Meaning the
users. From confusion.)

templates/next/sidebar.tpl

@@ -0,0 +1,14 @@
+{if $is_raw_mode}
+<div id="serendipity{$pluginside}SideBar">
+{/if}
+{foreach from=$plugindata item=item}
+	<section class="widget {$item.class}">
+    {if $item.title != ""}
+    	<h3>{$item.title}</h3>
+	{/if}
+    	{$item.content}
+    </section>
+{/foreach}
+{if $is_raw_mode}
+</div>
+{/if}