score_parallel.py: fix flexibility scoring.
score_parallel.py: fix flexibility scoring.

Forgot to pass the half_file to bzcat when doing flexibility scoring.

moses-smt/mosesdecoder,pjwilliams/mosesdecoder,tofula/mosesdecoder,tofula/mosesdecoder,emjotde/mosesdecoder_nmt,emjotde/mosesdecoder_nmt,alvations/mosesdecoder,moses-smt/mosesdecoder,moses-smt/mosesdecoder,tofula/mosesdecoder,alvations/mosesdecoder,emjotde/mosesdecoder_nmt,moses-smt/mosesdecoder,tofula/mosesdecoder,alvations/mosesdecoder,moses-smt/mosesdecoder,pjwilliams/mosesdecoder,pjwilliams/mosesdecoder,pjwilliams/mosesdecoder,emjotde/mosesdecoder_nmt,emjotde/mosesdecoder_nmt,tofula/mosesdecoder,moses-smt/mosesdecoder,moses-smt/mosesdecoder,alvations/mosesdecoder,pjwilliams/mosesdecoder,emjotde/mosesdecoder_nmt,emjotde/mosesdecoder_nmt,pjwilliams/mosesdecoder,emjotde/mosesdecoder_nmt,emjotde/mosesdecoder_nmt,tofula/mosesdecoder,tofula/mosesdecoder,alvations/mosesdecoder,alvations/mosesdecoder,alvations/mosesdecoder,moses-smt/mosesdecoder,alvations/mosesdecoder,tofula/mosesdecoder,pjwilliams/mosesdecoder,alvations/mosesdecoder,alvations/mosesdecoder,tofula/mosesdecoder,moses-smt/mosesdecoder,moses-smt/mosesdecoder,pjwilliams/mosesdecoder,tofula/mosesdecoder,emjotde/mosesdecoder_nmt,moses-smt/mosesdecoder,pjwilliams/mosesdecoder,alvations/mosesdecoder,tofula/mosesdecoder,pjwilliams/mosesdecoder