Indicate type of array for array options in rule option lists

[bmish]

Before:

Name	Description	Type
classNames	Some list of classes...	Array

After:

Name	Description	Type
classNames	Some list of classes...	String[]

With meta.schema:

{
  "type": "object"
  "properties": {
    "classNames": {
      {
        "type": "array"
        "items": {
          "type": "string"
        }
      }
    }
  }
}

Part of:

• Various improvements to rule option lists #491