remove a test that fail for not implemented feature as the original case is now tested in other tests

fixed optimization bugs triggered by propagation of shape 1 to unbroadcastable dims - hint: prefer broadcast_like() to alloc()

Updated Windows install instructions to say GPU does not work, also replaced refs to Python 2.7 by Python 2.6 because Python(x,y) is currently using 2.6

Fixed check of the existence of the cuda_ndarray module under Windows, where the extension is not .so

Fixed a bug reported by cityhall consisting in not calling tensor.as_tensor on arguments before calling make_node

implement/test the proposal that created shared variable must return the same type as what they received as input.