Updated spare capacity management model, added OpenAPI support, Added iSCSI properties for CHAP, Event usage enhancements and guidance and Volume schema updates

• Updated Enhanced Spare Capacity Management Model
• Deprecated Remaining Capacity
• Added OpenAPI support: schema references and OpenAPI YAML files
• Added iSCSI properties for CHAP
• Event usage enhancements and guidance
• Volume schema updates – RAID Type enum (deprecating VolumeType usage), add ReplicaTargets