- adds `jsgrammar.LINETERMINATORSEQ_RE`
- lexer `tstream.TokenStream` checks for lineterminators in tokens
- adds `tstream.Token`
- refractors `tstream.TokenStream` and `jsparser.Parser` and to use it
* direct execution comment accidental removal
* zip type check in 'traverse'
* less convoluted 'variables' in JSInterpreter initialization
* tiny bit more meaningful log messages
* changing single letter flags to more explanatory names
* refactoring skip test logic