Add caveat to benchmarks

[kamikazechaser]

I think it should be mentioned that Rayo storm takes advantage of all CPU's in the benchmarks (Which is kind of an unfair advantage imho in a fair benachmarking process). Kind of misleading for people who open the page.

[aichholzer]

@kamikazechaser -Good point. Given the description of the benchmark, I would expect people to read up on what Rayo/Storm means and make their own conclusions.

[aichholzer]

@kamikazechaser https://github.com/GetRayo/rayo.js/commit/1b67eeeb9eed41070d1adbcb683e3274aaac5e4b