There are some problems in reproducing the results of fine_grained

[felixfuu]

1. https://penzhanwu2v2.blob.core.windows.net/data/htzhang/coco/annotations/lvis_od_train.json This file has expired and cannot be downloaded, could you re-upload it?
2. The probability_drop_positive is set to 0.2 (config ), but it is forced to 0. in generate_control_options_given_probabilities ( code ). is this a bug? @ashkamath @zdou0830