version: character
data_loading: boolean
data_loading_header: boolean
data_ignore: character
cache_loading: boolean
recursive_loading: boolean
munging: boolean
logging: boolean
logging_level: character
load_libraries: boolean
libraries: character
as_factors: boolean
tables_type: character
attach_internal_libraries: boolean
cache_loaded_data:  boolean
sticky_variables: character
underscore_variables: boolean
cache_file_format: character
