Removed outdated spec from meta_datum_spec
Fix set_meta_data
Fix spec meta_datum_keywords_spec
Added get_meta_datum_class to MetaKey instance
Fixed meta_data creation part of typo_madek_player_plugin_request_spec;

reading is still broken it seems to rely on our hack
set_meta_data accepts hashes with string keys to
Fix title_meta_datum_spec
Reenabled the hack in the MetaDatum initializer

and adjust it