public.json: Add 'GET /people' and 'GET /person/{id}' endpoints

The new endpoints are copied from the trip endpoints, changing 'trip'
-> 'person' and 'trips' -> 'people'.
public.json: Add 'person' query parameter to 'GET /drops'

So you can find the drops for a particular person.
public.json: Standardize on 'ID' (vs 'id') in descriptions
public.json: Add 'GET /addresses' and 'GET /address/{id}' endpoints

The new endpoints are copied from the trip endpoints, changing 'trip'
-> 'address', 'trips' -> 'addresses', and replacing 'route' filtering
with 'person' filtering.