[Code Style] Cleaning up code for `vsboost` benchmark.
[Code Style] Performance benchmark: removed unused code.
[Code Style] Performance benchmark: different cases are now triggered by specifying its macro (not ideal, I guess).
[Performance] String formatter performance is increased by 10-15% by using attachable string stream.
[Aux] Synchronizing code with listed changes.
[Code Style] Tiny refactoring over value mappers and extractors.
[Task] One task less.