"Named entities" is the NLP jargon for proper nouns which
represent people, places, organisations, and so on.

This module provides a very simple way of extracting these from a text.
If we run the "extract_entities" routine on a piece of news coverage of
recent UK political events, we should expect to see it return a list of
hash references looking like this:

{ entity => 'Mr Howard', class => 'person', scores => { ... }, },
{ entity => 'Ministry of Defence', class => 'organisation', ... },
{ entity => 'Oxfordshire', class => 'place', ... },

The additional "scores" hash reference in there breaks down the various
possible classes for this entity in an open-ended scale.