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-generator/src/node/parentheses.js

@@ -82,7 +82,8 @@ export function Binary(node: Object, parent: Object): boolean {
       return true;
     }
 
-    if (parentPos === nodePos && parent.right === node) {
+    // Logical expressions with the same precedence don't need parens.
+    if (parentPos === nodePos && parent.right === node && !t.isLogicalExpression(parent)) {
       return true;
     }
   }
@@ -119,6 +120,10 @@ export function SequenceExpression(node: Object, parent: Object): boolean {
     return false;
   }
 
+  if (t.isReturnStatement(parent)) {
+    return false;
+  }
+
   // Otherwise err on the side of overparenthesization, adding
   // explicit exceptions above if this proves overzealous.
   return true;

packages/babel-generator/src/node/whitespace.js

@@ -163,7 +163,8 @@ exports.nodes = {
  * Test if Property or SpreadProperty needs whitespace.
  */
 
-exports.nodes.Property =
+exports.nodes.ObjectProperty =
+exports.nodes.ObjectMethod =
 exports.nodes.SpreadProperty = function (node, parent) {
   if (parent.properties[0] === node) {
     return {