Workflow documentation is now in infra-manual

Replace URLs for workflow documentation to appropriate parts of the
OpenStack Project Infrastructure Manual.

Change-Id: Id09c9bdf8804c1ed90e49606e76ffbff1d96a7c2
Merge "Workflow documentation is now in infra-manual"
Followup for ec2 credentials command fix

Add functional tests for 'ec2 credentials' commands.

Also fix tenant_id in output for create and show.

Change-Id: I6ba3249b67408571624709e17f8aa2ac6d80237d
Merge "Followup for ec2 credentials command fix"