1. Check for nullptr if metadata is set. 2. Changing scaling_factor to be multiplied instead of divided (dcdb nomenclature).

Removing puning of ints to doubles and viceversa, and implementing use of scaling factor from metadata

SMUCNGPerf Operator: implementing memory bandwidth. PerSystSql Operator: fixing issue with one unit not being present, and no calculation was done.

- Hierarchical units are now supported across the framework in all plugins

- The configurator now accounts for hierarchical units
- Added checks in existing plugins to enforce flat/hierarchical units
- DISCLAIMER: this has likely broken the framework until I refactor OperatorTemplate

- When a unit cannot be built, UnitGenerator does not abort anymore;
error log messages are produced, and it proceeds with the next unit