Refine query-bid.py, add cuda_set_device(2) and reduce gpu memory usage between loading cuda_query_metrix and cuda_bidword_metrix.
Refine query-bid.py, add cuda_set_device(2) and reduce gpu memory usage between loading cuda_query_metrix and cuda_bidword_metrix.

SnakeHunt2012/word2vec,SnakeHunt2012/word2vec,SnakeHunt2012/word2vec,SnakeHunt2012/word2vec,SnakeHunt2012/word2vec