minor spelling fix (#663)

* minor spelling fix

* Update common_layers.py

* Update common_layers.py

* Update transformer.py

Author: cbockman

tensor2tensor/layers/common_layers.py

@@ -630,7 +630,7 @@ def layer_preprocess(layer_input, hparams):
 
   See layer_prepostprocess() for details.
 
-  A hyperparemeters object is passed for convenience.  The hyperparameters
+  A hyperparameters object is passed for convenience.  The hyperparameters
   that may be used are:
 
     layer_preprocess_sequence
@@ -666,7 +666,7 @@ def layer_postprocess(layer_input, layer_output, hparams):
 
   See layer_prepostprocess() for details.
 
-  A hyperparemeters object is passed for convenience.  The hyperparameters
+  A hyperparameters object is passed for convenience.  The hyperparameters
   that may be used are:
 
     layer_postprocess_sequence
@@ -1289,7 +1289,7 @@ def relu_density_logit(x, reduce_dims):
   Useful for histograms.
 
   Args:
-    x: a Tensor, typilcally the output of tf.relu
+    x: a Tensor, typically the output of tf.relu
     reduce_dims: a list of dimensions
 
   Returns:

tensor2tensor/models/transformer.py

@@ -704,7 +704,7 @@ def transformer_encoder(encoder_input,
               common_layers.layer_preprocess(x, hparams), hparams, pad_remover,
               conv_padding="SAME", nonpadding_mask=nonpadding)
           x = common_layers.layer_postprocess(x, y, hparams)
-    # if normalization is done in layer_preprocess, then it shuold also be done
+    # if normalization is done in layer_preprocess, then it should also be done
     # on the output, since the output can grow very large, being the sum of
     # a whole stack of unnormalized layer outputs.
     return common_layers.layer_preprocess(x, hparams)