Link in the blocksparse docs and add a section about the gpuarray backend.

doc/library/sandbox/gpuarray/index.txt

+
+.. _libdoc_gpuarray:
+
+=======================================================
+:mod:`theano.sandbox.gpuarray` -- The (new) GPU backend
+=======================================================
+
+.. module:: theano.sandbox.gpuarray
+   :platform: Unix, Windows
+   :synopsis: Code for GPU programming (new)
+.. moduleauthor:: MILA
+
+.. toctree::
+    :maxdepth: 1
+
+    type

doc/library/sandbox/gpuarray/type.txt

+.. _libdoc_gpuarray_type:
+
+===================================================
+:mod:`theano.sandbox.gpuarray.type` -- Type classes
+===================================================
+
+.. automodule:: theano.sandbox.gpuarray.type
+   :members:

doc/library/sandbox/index.txt

@@ -14,6 +14,8 @@
     :maxdepth: 1
 
     cuda/index
+    gpuarray/index
     linalg
     neighbours
     rng_mrg
+    blocksparse