NVBench instrumented benchmarks should always include bulk data in JSON output

[oleksandr-pavlyk]

At the moment, NVBench-instrumented benchmarks support --json result.json to output JSON file with benchmark summaries, and --jsonbin result.json to also output sidecar binary files with bulk data of individual measurements.

@gevtushenko suggested that --json result.json should always includes bulk data, and that --jsonbin option should become obsolete, be undocumented and eventually removed.