Instead of picking between several options, we simply have one line that gets filled
based on perspective.

Everything described as 'first person' was really second person, so that has
been updated. Words can now be set to be objective, which is needed for first-person
pronouns to appear correctly

This is necessary to move away from the POVPair/etc. classes; verbs need to be
conjugated correctly for the subject they refer to. For example, 'You gulp' vs
'She gulps'

The name and pronouns properties now check the entity's perspective, returning
specific ones for first person. This also includes a class for using a pronoun as
a noun.

Each RandomWord instance now shares its history with anything derived
from it (e.g. by getting the capitalized version of that instance).
This ensures that repetition doesn't occur.