6.0.0

I'm extremely stupid and didn't commit as I go. To anyone reading this
I'm extremely sorry. A lot of these changes are very broad and I plan on
releasing Babel 6.0.0 today live on stage at Ember Camp London so I'm
afraid I couldn't wait. If you're ever in London I'll buy you a beer
(or assorted beverage!) to make up for it, also I'll kiss your feet and
give you a back massage, maybe.

packages/babel-cli/src/babel-node.js

@@ -18,7 +18,7 @@ if (argSeparator > -1) {
   babelArgs = babelArgs.slice(0, argSeparator);
 }
 
-getV8Flags(function (v8Flags) {
+getV8Flags(function (err, v8Flags) {
   babelArgs.forEach(function(arg){
     let flag = arg.split("=")[0];