This PR has refined the benchmarking tool and data files some of which are incorporated from the miroyip/nativejson-benchmark repository.
Also, rapidyaml used there has been updated from 0.6.0 to 0.7.0 which includes huge parser improvements, and rapidyaml usages with mutable buffers have been fixed (I didn't fully understand how it worked at the time I introduced the tool).

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• Changes are described in the pull request or in a referenced issue.
• The test suite compiles and runs without any error.
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• The C++11 support varies between different compilers and versions. Please note the list of supported compilers. Some compilers like GCC 4.7 (and earlier), Clang 3.3 (and earlier), or Microsoft Visual Studio 13.0 and earlier are known not to work due to missing or incomplete C++11 support. Please refrain from proposing changes that work around these compiler's limitations with #ifdefs or other means.
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