Added __float2half_rn() and __half2float()

AlexeyAB

2018-02-22 b2b5756d86670b787dac440020922eeb5e8a1442

 cfg/darknet19_448.cfg

@@ -1,6 +1,8 @@
[net]
batch=128
subdivisions=4
#batch=128
#subdivisions=4
batch=1
subdivisions=1
height=448
width=448
max_crop=512