message: Fixing some capitalization
  In working through the tutorial it looks like there no `lexer` property of `chevrotain` just `Lexer`
diff: @@ -59,7 +59,7 @@ accomplished by marking them with the SKIP group.
  const WhiteSpace = createToken({
  name: "WhiteSpace",
  pattern: /\s+/,
  - group: chevrotain.lexer.SKIPPED,
  + group: chevrotain.Lexer.SKIPPED,
  line_breaks: true
  });
  ```
  @@ -90,7 +90,7 @@ const LessThan = createToken({name: "LessThan", pattern: />/});
  const WhiteSpace = createToken({
  name: "WhiteSpace",
  pattern: /\s+/,
  - group: chevrotain.lexer.SKIPPED,
  + group: chevrotain.Lexer.SKIPPED,
  line_breaks: true
  });
  ```
  