fixed 1929:cannot acess appadmin cache if you use redis as cache, thanks leonardo

VERSION

@@ -1 +1 @@
-Version 2.9.5-trunk+timestamp.2014.05.26.23.42.22
+Version 2.9.5-trunk+timestamp.2014.05.26.23.47.54

gluon/contrib/gae_memcache.py

@@ -21,6 +21,9 @@ class MemcacheClient(object):
         self.request = request
         self.default_time_expire = default_time_expire
 
+    def initialize(self):
+        pass
+
     def __call__(
         self,
         key,

gluon/contrib/redis_cache.py

@@ -105,6 +105,9 @@ class RedisClient(object):
 
         self.r_server = redis.Redis(host=host, port=port, db=self.db, password=self.password)
 
+    def initialize(self):
+        pass
+
     def __call__(self, key, f, time_expire=300, with_lock=None):
         if with_lock is None:
             with_lock = self.with_lock