OneDRS: Enable balancing by storage space #7930

Description
When balancing workload, storage space should be taken into account, according to the related user defined weight.

Use case
Together with disk I/O, storage space balancing enables storage optimization. The weight associated to the storage space will be taken into account when formulating the objective for the balancing policy.

Interface Changes

• Sunstone: Infrastructure/Clusters/OneDRS -> Update Configuration should get the field for storage space balancing weight
• OneDRS configuration file might containt the same weight value

Progress Status

• Code committed
• Testing - QA
• Documentation (Release notes - resolved issues, compatibility, known issues)