Set strict SSL to false for node 0.6.

Per https://github.com/travis-ci/travis-ci/issues/1785#issuecomment-31556337
Adding a banner message about turning off strict SSL
Making a separate method for disabling strict SSL, so the meaning is more explicit
Using String#split instead of Gem::Version comparison, per https://github.com/travis-ci/travis-build/pull/188/files#r8655284