block lambda revival

[Brendan Eich]

As promised/threatened: http://wiki.ecmascript.org/doku.php?id=strawman:block_lambda_revival

No GLR parser required (destructuring and left-hand side of assignment still want it for a precise grammar).

I'll work on semantics for the new productions and builtin Block object.

As noted in the prologue, I think we should do arrow function syntax and not (ever) this strawman, or block lambda revival and not (ever) arrow function syntax. Comments welcome.

/be