Reports return a hash key not id

Note: When merged, this needs cherry-picking for branches 1.1.x, 1.2.x and 1.3.x as well I believe.

This patch fixes the documentation and some inline comments to reflect that
a report returns a "hash" key not an "id" and that the type is a hash, not
a uuid in this instance.

Signed-off-by: Ken Barber <ken@bob.sh>