-  set_portray_text(+Key, +Value) is det
 
-  set_portray_text(+Key, ?Old, +New) is det
 - Set options for portraying. Defined Keys are:
- enabled
 - Enable/disable portray text
 
- min_length
 - Only consider for conversion lists of integers
that have a length of at least Value. Default is 3.
 
- ellipsis
 - When converting a list that is longer than Value, display
the output as 
start...end.