Merge pull request #306 from chainer/typo

fixes minor typos

Author: toslunar

chainerrl/replay_buffer.py

@@ -98,7 +98,7 @@ def sample_episodes(self, n_episodes, max_len=None):
                 episode is sampled instead. If None, full episodes are always
                 returned.
         Returns:
-            Sequence of n sampled epiosodes, each of which is a sequence of
+            Sequence of n sampled episodes, each of which is a sequence of
             transitions.
         """
         raise NotImplementedError
@@ -164,7 +164,7 @@ def stop_current_episode(self):
 
 
 class PriorityWeightError(object):
-    """For propotional prioritization
+    """For proportional prioritization
 
     alpha determines how much prioritization is used.