Summary: This does nothing fancy, just closes the resource and releases/breaks leases. They'll get cleaned up in some to-be-written GC process.
Test Plan: Closed resources from web UI and CLI.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T2015
Differential Revision: https://secure.phabricator.com/D3998
