in BLK, allow @@ to print literal @. half of #23
Fix failing decompilation test

Apparently V8 now hardens script injection into the Function constructor
by adding a /**/ to the end of a .toString()'ed function.

Info:

https://groups.google.com/forum/#!topic/nodejs/meIFcWhoGqM
https://code.google.com/p/google-caja/issues/detail?id=1616