[webkit-dev] Please install shellwords on the bots

[Filip Pizlo]

This bug: https://bugs.webkit.org/show_bug.cgi?id=120696

Is for making run-javascriptcore-tests run all of the tests in parallel and in a way that is aware of our multiple tiers.  It vastly improves JSC test coverage.

Right now, the script will refuse to do anything if your machine doesn't have the Ruby shellwords package installed.  Eventually I'll change that to make it just fail.

Please install shellwords on the bots so that this script can work.

(And no, I don't see an easy alternative to using shellwords for this testing infrastructure.  It would take a lot more code if we didn't want to use shellwords.  So, you should install shellwords to run javascriptcore tests.  It's already installed by default on a lot of OS's.)

I'll be landing this patch soon.  We need the test coverage.

-Filip