Create app/packages symlink.
Add app/build script.
Update path for analyzer_experimental in function_body_visitor.dart
app.js is not under app/
Update .gitignore
Added testdata/todomvc.

todomvc/js/model.js is the translated version of todomvc/dart/model.dart.
Merge remote-tracking branch 'chbridge/master'
Fixup app/build