Small bug about NonLocalResNet34/50/.... ？

[leeguandong]

when use depth>18, will have a bug.
In _redidual_block:
def _residual_block(block_function, filters, blocks, stage,
transition_strides=None, transition_dilation_rates=None,
dilation_rates=None, is_first_layer=False, dropout=None,
residual_unit=_bn_relu_conv):
if transition_dilation_rates is None:
transition_dilation_rates = [(1, 1)] * blocks
if transition_strides is None:
transition_strides = [(1, 1)] * blocks
if dilation_rates is None:
dilation_rates = [(1, 1)] * blocks
Adding the last two lines of code above is necessary.

[titu1994]

Would you like to add a PR for this ? Or should I merge it directly ?