Removed unnecessary return statements
Refined how spaces are described

Removed override of inherited describe() method from the
Describable class in Space in favor of using the describe
method from the narrator class. Added a default toString method
to the narrator class, which uses no article.

Also changed the way the 'look' action behaves: when asked to
describe rooms, the server sends two notifications: one, the name
of the room (in all capitals) and the description on the second.
Refined the 'who' action