Some script parser changes.

This PR contains 5 changes, as usual feel free to cherry-pick only some of them:

 - remove a debug dump() in the case of `@noframes`
 - the two grammar simplifications I already mentioned in the discussion of #1996 (return only the actual locale without colon from the parser and use `$` instead of `val.join('')` to get the matched string)
 - fix an undefined variable access when a script contains a localized name/description
 - use the external extractMeta module in parseScript.js instead of redefining that function (I guess this was a silent merge conflict)