tools,benchmark: increase lint compliance

In the hopes of soon having the benchmark code linted, this change
groups all the likely non-controversial lint-compliance changes such as
indentation, semi-colon usage, and single-vs.-double quotation marks.

Other lint rules may have subtle performance implications in the V8
currently shipped with Node.js. Those changes will require more careful
review and will be in a separate change.

PR-URL: https://github.com/nodejs/node/pull/5429


Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Brian White <mscdex@mscdex.net>