rbx head no longer needs default-version args and 1.9 is default anyway.

So remove the 1.9 default assumption.
Update to what the latest versions of jruby/ruby/perl are.
Add a versions.sh script that outputs eval()'able strings for helper.sh
Have helper.sh use versions.sh for subscript smoketest simplification.
Lets start tdding this crappy script and make some perl modules out of it.
Ok, improve the smoketests a bit so they're less derp/churny.

Use the web-versions link instead of installing jruby/nokogiri to get
latest versions from the web.