Controller nodes left in /etc/swift/object.builder after deletion from the cluster

[Egor Kotko]

Steps to reproduce:
1) Create env: Ubuntu 5 controllers 1 compute, deploy
2) Delete 3 controllers (primary and 2 last added), deploy
3) Execute on primary controller command:
swift-ring-builder /etc/swift/object.builder
http://paste.openstack.org/show/327923/

list of nodes in the cluster:
http://paste.openstack.org/show/328055/

Actual result:
Deleted controllers left in the list of swift-ring-builder

Version info:
{"build_id": "2015-06-19_13-02-31", "build_number": "525", "release_versions": {"2014.2.2-6.1": {"VERSION": {"build_id": "2015-06-19_13-02-31", "build_number": "525", "api": "1.0", "fuel-library_sha": "2e7a08ad9792c700ebf08ce87f4867df36aa9fab", "nailgun_sha": "dbd54158812033dd8cfd7e60c3f6650f18013a37", "feature_groups": ["mirantis"], "openstack_version": "2014.2.2-6.1", "production": "docker", "python-fuelclient_sha": "4fc55db0265bbf39c369df398b9dc7d6469ba13b", "astute_sha": "1ea8017fe8889413706d543a5b9f557f5414beae", "fuel-ostf_sha": "8fefcf7c4649370f00847cc309c24f0b62de718d", "release": "6.1", "fuelmain_sha": "a3998372183468f56019c8ce21aa8bb81fee0c2f"}}}, "auth_required": true, "api": "1.0", "fuel-library_sha": "2e7a08ad9792c700ebf08ce87f4867df36aa9fab", "nailgun_sha": "dbd54158812033dd8cfd7e60c3f6650f18013a37", "feature_groups": ["mirantis"], "openstack_version": "2014.2.2-6.1", "production": "docker", "python-fuelclient_sha": "4fc55db0265bbf39c369df398b9dc7d6469ba13b", "astute_sha": "1ea8017fe8889413706d543a5b9f557f5414beae", "fuel-ostf_sha": "8fefcf7c4649370f00847cc309c24f0b62de718d", "release": "6.1", "fuelmain_sha": "a3998372183468f56019c8ce21aa8bb81fee0c2f"}

[Aleksandr Didenko (adidenko)]

We need to remove servers from swift rings when we remove controllers:
http://docs.openstack.org/developer/swift/admin_guide.html#managing-the-rings