listed with --lmfile options. Also the LM that is automatically created
when the --corpus option is included.
enhance robustness and messaging for command-line usage
improve --srilm-bin SRILM handling
remove kenlm stuff. That can be accomplished outside this script.
moved unit tests to separate file:
because the mock module couldn't be found.
make merge_lms.py executable
add merge-lms step to pipeline.pl