Load gherkin parser considering language comment

Basic support for i18n.

Problem is all languages but not EN throwing that error:

```
/Users/vyacheslav/Code/cucumber-js/node_modules/gherkin/lib/gherkin/lexer/ru.js:1614
 throw "Lexing error on line " + this.line_number + ": '" + content + "'. See 
                                                                    ^
Lexing error on line 2: 'Функционал: Сложение чисел'. See http://wiki.github.com/cucumber/gherkin/lexingerror for more information.
```

I'm think problem in generated gherkin lexers.
But I can't find where is problem because generated lexers isn't readable by normal human.