Cleanup server via ID instead of name
Cleanup server via ID instead of name

- name is no longer unique

Signed-off-by: Felix Riegger <9c2aa7530239a330bbac6ac4f56e0946781dfd29@sap.com>

cloudfoundry-incubator/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release