fix new crash due to import of scipy.sparse.

theano/sparse/type.py

 import numpy
 try:
-    import scipy
+    import scipy.sparse
     imported_scipy = True
 except ImportError:
     imported_scipy = False
@@ -8,6 +8,7 @@ except ImportError:
 import theano
 from theano import gof
 
+
 def _is_sparse(x):
     """
     @rtype: boolean