_metadict is a dict that work with not hashable type. This is needed
for the SliceType.

This is needed for scan optimization to rebuild the node outside the scan.

FIX: tutorial pycuda <> theano compatibility

Warning

thunk needs lazy attribute

Algorithm Speed Up

CumsumOp on GPU

Fix one problem related to strides by copying the strides infos
from the input to the output.

Added __eq__ and __hash__ methods.
Fixed c_code_cache_version
Check if axis=None before bailing out.