Now, running protractor configs by default only runs e2e tests. If
the --benchmark flag is added, it runs only the perf tests, and always
restarts the browser in between tests. If the --dryrun test is added,
the perf tests are run only once.
This should make it easier to run perf tests versus example e2e tests,
and help stabilize the travis build because perf tests always
run with a clean browser.
