Fix deployment.check api
Fix deployment.check api

rally.api.Deployment.check was adopted to use environment manager whereis
traceback is optional in case of errors, but it had not been taken into
accaunt

Change-Id: I8b7c42aa77664a5b3a04aeb2b391cbadf2756dd4

openstack/rally,openstack/rally,openstack/rally,openstack/rally