Update benchmark.js

From the documentation I presumed that the following would allow me to specify a minSamples value:

...........
		.run({
			'async' : false,
			'minSamples' : 200
		});
...........

however the default was always 5. Adding the code in this commit means the minSamples value is now picked up and used. If it is not specified the previous default of 5 is used. I was running my code in a browser with the last release v1.0.0.