Move and fix the doc of blocksparse

doc/library/sandbox/blocksparse.txt → doc/library/tensor/nnet/blocksparse.txt

 .. _libdoc_blocksparse:
 
-===========================================================================
-:mod:`sandbox.blocksparse` --  Block sparse dot operations (gemv and outer)
-===========================================================================
+===============================================================================
+:mod:`blocksparse` --  Block sparse dot operations (gemv and outer)
+===============================================================================
 
-.. module:: sandbox.blocksparse
+.. module:: tensor.nnet.blocksparse
    :platform: Unix, Windows
    :synopsis: Block sparse dot
 .. moduleauthor:: LISA
 
-API
-===
 
-.. automodule:: theano.sandbox.blocksparse
+.. automodule:: theano.tensor.nnet.blocksparse
     :members:

theano/tensor/nnet/blocksparse.py

@@ -18,7 +18,7 @@ class SparseBlockGemv(Op):
 
     where b, h, W, o iIdx, oIdx are defined in the docstring of make_node.
 
-    .. image:: ../../images/blocksparse.png
+    .. image:: ../../../images/blocksparse.png
         :scale: 50 %
 
     """