Allow saving multiple named profiles

[Tyriar]

Repro:

Debug some JS with this:

		console.profile('start');
...
		console.profileEnd('start');
		console.profile('end');
...
		console.profileEnd('end');

Resulting files:

Profile in devtools:

[Tyriar]

Didn't see the files in the original report, but anyway I would hope that we track runs like in devtools. The simple way would be calling them something like start (n)?