Small speedups. Added index on the name column for tag

boards/models/tag.py

@@ -32,7 +32,7 b' class Tag(models.Model):'
     class Meta:
         app_label = 'boards'
 
-    name = models.CharField(max_length=100)
+    name = models.CharField(max_length=100, db_index=True)
     threads = models.ManyToManyField(Thread, null=True,
                                      blank=True, related_name='tag+')
     linked = models.ForeignKey('Tag', null=True, blank=True)

boards/templates/boards/post.html

@@ -79,7 +79,7 b''
             {% endif %}
         </div>
     {% endcache %}
-        {% if is_opening and thread.tags.exists %}
+        {% if is_opening %}
         {% cache 600 post_thread thread.id thread.last_edit_time LANGUAGE_CODE need_open_link %}
             <div class="metadata">
                 {% if is_opening and need_open_link %}