[doc] Update RESOURCES document

Remove obsolete 'strategy' sections from resources descriptions.
Emphasize API-based approach to migration of meta-resources and workload
resources.
Fix hyperlink in USAGE document.
Adds minor updates to formatting
Reverts broken formatting
Change argument name in create_network.
Unstash network delete function
pep8 fixes
Neutron reset implementation in management.cleanup
[doc] Add API specification document
[doc] Minor update to RESOURCES document
[doc] WORKLOADS document initial version

WORKLOADS.md contains document that describes types of workloads supported and
planned for support in Pumphouse.
Merge remote-tracking branch 'origin/master' into cinder-resources