Added documentaition for for tensor/utils.py

doc/library/tensor/index.txt

@@ -22,3 +22,4 @@ They are grouped into the following sections:
     raw_random
     shared_randomstreams
     signal/index
+    utils

doc/library/tensor/utils.txt

+===================================================================
+:mod:`tensor.utils` --  Tensor Utils
+===================================================================
+
+.. module:: tensor.utils
+   :platform: Unix, Windows
+   :synopsis: Tensor Utils
+.. moduleauthor:: LISA
+
+.. automodule:: theano.tensor.utils
+    :members:
+