fix name for average embed inp

Author: zsdonghao

example/tutorial_imdb_fasttext.py

@@ -71,7 +71,7 @@ def __init__(self, vocab_size, embedding_size, n_labels):
             tf.int32, shape=[None], name='labels')
 
         # Network structure
-        network = AverageEmbeddingInputLayer(
+        network = AverageEmbeddingInputlayer(
             self.inputs, self.vocab_size, self.embedding_size)
         self.network = DenseLayer(network, self.n_labels)