Move TensorType to its own file as CudaNdarrayType and SparseType.

theano/gof/__init__.py

@@ -78,4 +78,4 @@ from theano.gof.type import \
     Type, Generic, generic
 
 from theano.gof.utils import \
-    object2, MethodNotDefined
+    hashtype, object2, MethodNotDefined

theano/gof/utils.py

@@ -22,6 +22,11 @@ def hashgen():
 hashgen.next = 0
 
 
+def hashtype(self):
+    t = type(self)
+    return hash(t.__name__) ^ hash(t.__module__)
+
+
 class MethodNotDefined(Exception):
     """
     To be raised by functions defined as part of an interface.