reddit: make the cache timeout configurable

And decrease poll time

tipbot/config.py.example

@@ -57,9 +57,10 @@ network_config = {
     'login': 'testbx',
     'keyword': '/u/testbx',
     'user_agent': tipbot_name,
-    'update_period': 90,
+    'update_period': 35,
     'load_limit': 100,
     'use_unread_api': True,
+    'cache_timeout': 30,
   },
   'twitter': {
     'login': 'tipperome',

tipbot/modules/reddit.py

@@ -51,8 +51,9 @@ class RedditNetwork(Network):
       self.load_limit=cfg['load_limit']
       self.keyword=cfg['keyword']
       self.use_unread_api=cfg['use_unread_api']
+      self.cache_timeout=cfg['cache_timeout']
 
-      self.reddit=praw.Reddit(user_agent=user_agent)
+      self.reddit=praw.Reddit(user_agent=user_agent,cache_timeout=self.cache_timeout)
       self.reddit.login(self.login,password)
       self.items_cache=dict()