documentation update and docstrings

tiramisu/storage/dictionary/storage.py

@@ -46,6 +46,11 @@ class Cache(object):
         return False, None
 
     def hascache(self, cache_type, opt):
+        """ option is in the cache
+
+        :param cache_type: value | property
+        :param opt: the key (typically, the option object)
+        """
         return opt in self._cache
 
     def reset_expired_cache(self, cache_type, exp):
@@ -56,6 +61,7 @@ class Cache(object):
                 del(self._cache[key])
 
     def reset_all_cache(self, cache_type):
+        "empty the cache"
         self._cache.clear()
 
     def get_cached(self, cache_type, context):