Change type of X-Openstack-Request-Id
Change type of X-Openstack-Request-Id

This patch changes 'request_id' type from 'type:UUID' to 'type:string'.

Change-Id: Ife661ec8b5f76c5498bcad26f25df05c566a51c9

openstack/senlin,stackforge/senlin,openstack/senlin,openstack/senlin,stackforge/senlin