Fix summary plugin not properly updating asset paths in summaries.

RST files with figures in the summary were not properly displaying the image, because the path was not properly being rewritten with the "|filename|" substituted with the proper path.

Calling _update_content() performs the proper regex substitutions.

summary/summary.py

@@ -54,7 +54,7 @@ def content_object_init(instance):
                             len(instance.settings['SUMMARY_BEGIN_MARKER'])
                             if begin_summary != -1 else 0)
             end_summary = end_summary if end_summary != -1 else None
-            instance._summary = content[begin_summary:end_summary]
+            instance._summary = instance._update_content(content[begin_summary:end_summary], instance._context.get('localsiteurl', ''))
 
 def register():
     signals.initialized.connect(initialized)