Document how to run benchmark.js

[jdmarshall]

The Benchmark.js home page shows how to write a test suite, but at no point does it show how to run the test suite and get results.

There is no bin, as you would get with testing frameworks, so my best guess at the correct answer was:

lib/settings/index.bench.js

But this only results in a few lines of console code from the code under test and then nothing. No statistics, no output files.

Stepping through in a debugger, the code is definitely running. It's just not accomplishing anything.

[EmilyRagan]

I definitely agree that this should be on the main page. I found this library through this article, which says to just run it with node yourBenchmarkFile.js, which works for me.