add acorn
remove unneeded start end offsets
add let and const
Literal type isn't helpful
start modifying parsejs
mostly works
generates same output
fix EmptyStatement transformation
add label support to break
allow ✖ instead of error nodes
update error recovery tests for ✖ change

 and temporarily disable some of them
update acorn
Hand-check and update remaining error recovery checks
Merge pull request #13 from ajaxorg/acorn

Use Acorn