+ support splitting of config yml to multiple files
+ add set and get to create in-memory lookup
+ support marc_remove('*')
++ fix-length fields (<100) support [2.29]
++ work without indexers installed or enabled [2.30]
++ simpliest possible conf/llin.yml as example
- load_ds/save_ds should use on-disk hash to preserve inodes
- leader(position,...), indicator(field,nr) nr=1|2 for MARC input
-- fix-length fields (<100) support
- validate should ignore modify_file
- add option to specify output marc path in config.yml
- add dBase input format