bots: Add basic metadata with failover, used on running only.

zulip_bots/zulip_bots/bots/wikipedia/wikipedia.py

@@ -18,6 +18,11 @@ class WikipediaHandler(object):
     kind of external issue tracker as well.
     '''
 
+    META = {
+        'name': 'Wikipedia',
+        'description': 'Searches Wikipedia for a term and returns the top article.',
+    }
+
     def usage(self):
         return '''
             This plugin will allow users to directly search

zulip_bots/zulip_bots/bots/xkcd/xkcd.py

@@ -14,6 +14,11 @@ class XkcdHandler(object):
     commands.
     '''
 
+    META = {
+        'name': 'XKCD',
+        'description': 'Fetches comic strips from https://xkcd.com.',
+    }
+
     def usage(self):
         return '''
             This plugin allows users to fetch a comic strip provided by