Permanently destroy Almanac properties with the destruction engine

Summary: As suggested in D14461.

Test Plan: Used ./bin/remove destroy on an Almanac service with properties attached, saw entries removed from the phabricator_almanac.almanac_property table.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D14490