Add documentation for multiple engines

Registered by Jason Dunsmore

There should be a document describing how the multiple engine feature works and how to use it in a Heat deployment.

Blueprint information

Status:
Complete
Approver:
None
Priority:
Undefined
Drafter:
None
Direction:
Needs approval
Assignee:
Jason Dunsmore
Definition:
Approved
Series goal:
None
Implementation:
Implemented
Milestone target:
None
Started by
Jason Dunsmore
Completed by
Jason Dunsmore

Related branches

Sprints

Whiteboard

Gerrit topic: https://review.openstack.org/#q,topic:bp/multi-engine-docs,n,z

Addressed by: https://review.openstack.org/63963
    Add documentation for multi-engine

Addressed by: https://review.openstack.org/63962
    Rename scaleout_apis.rst -> scale_deployment.rst

(?)

Work Items

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