Plugin？ Relu or PRelu

[zcc199710]

The original version of yolo uses LRelu. Why does your plugin use PRelu, which will have a little impact on the accuracy of the results, and now many caffe-yolov3 use Relu

[lewes6369]

The repo used LRelu, too.The comment in NvInferPlugin.h header which figures out the createPReLUPlugin function actually implemented as LeakyRelu not PRelu .I am not sure it is correct in recently version.