Switches from tenant_id to tenant_name since latter isn't preserved between resets
Host for evacuation and reassignment removed from the configuration.

For evacuation random host is picked. Additional check for # of hosts > 1.
For reassignment tests look for the host with blocked status.
Switches to tenant picking by mask instead of hard-coded one
Updates functional tests description
Switches from '' to null for action parameter dropping via events
Adds separate handler for error events; changes files encoding to utf8
Merge remote-tracking branch 'origin/master' into cinder-resources