Add ignore rule for pseudo-classes to max-nesting-depth

[jasonlemay]

Current problem

.class-depth-1 {
  .class-depth-2 {
    .class-depth-3 {
      text-decoration: none;

      &:hover { // <- This is considered 4th level of nesting
        color: red;
      }
    }
  }
}

As this will output:

.class-depth-1 .class-depth-2 .class-depth-3 {text-decoration: none}
.class-depth-1 .class-depth-2 .class-depth-3:hover {color: red}

Proposed solution
Could we consider adding ignore: ["pseudo-classes"] to max-nesting-depth? I'm really against nesting more than 3 levels down, but pseudo-classes should not be considered nesting, in my opinion. As right now anyway I could write .class-depth-3:hover and that would pass, producing the same compiled result.