Test more colorful default theme

[aeschli]

• any os @bpasero

From reactions in #1270 and #1470 and other issues, we learned that we have fans of both the classic Visual Studio dark and light themes as well as the more colorful version

So we decided to bring the colors back in new themes, 'Dark+' and 'Light+'.

In addition to 4 major colors in the Visual Studio themes (comments, strings, numbers and keywords) we now have again colors for

• control flow keywords
• type names
• function names
• variable and parameter names

Testing

• test that the Light (Visual Studio), Dark (Visual Studio), Light+ and Dark+ themes look good with
  • JavaScript
  • TypeScript
  • C#
    There are known bugs in the tokenizers, check out https://github.com/Microsoft/TypeScript-TmLanguage/issues and https://github.com/atom/language-csharp/issues before filing an issue.
• test the themes with other languages
• test that the colors match the definitions in Tune new colors added for dark+ & light+ themes #1943