Update opal's source to 0.5.5
Update module to run with Opal 0.5.5
Add opal stdlib and upudate core+parser
Add good defaults for rspec
Intercept and compile requires
Fix some stdout stuff (should be backported to opal)
Whitespace
Update gems and cleanup Gemfile
Rename opal.coffee to opal-node, avoid require.extensions
Backport LoadError
Add an helper to change working directory
Expose nodejs require() to opal
Fix File and Dir specs