trunk: changes to babel scripts: 1. using train_pnorm_fast.sh instead of train_pnorm.sh; 2. removing unused script for extended lexicon. Both tested.

git-svn-id: https://svn.code.sf.net/p/kaldi/code/trunk@4524 5e6a8d80-dfce-4ca6-a32a-6e07a63d50c8