benchmark: merge url.js with url-resolve.js

url.js was broken since it didn't use the common.js runner. This fixes
that issue by merging it with url-resolve.js, which also benchmarks
url.resolve.

PR-URL: https://github.com/nodejs/node/pull/5177


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>