Adding custom styles

[pioupia]

Describe

Custom styles should be added so that users can create their own themes, allowing a more aesthetic generation than the default theme.

Format type

For simplicity, the JSON type should be used.
A function can be created to check that it is correctly formed.

Example:

{
  "colors": {
    "window": {
      "backgroundColor": "",
      "defaultForegroundColor": "",
      "closeWindowColor": "",
      "closeWindowColorStroke": "",
      "minifyWindowColor": "",
      "minifyWindowColorStroke": "",
      "reduceWindowColor": "",
      "reduceWindowColorStroke": ""
    },
    "text": {
      "keyword": "",
      "boolean": "",
      "number": "",
      "string": "",
      "function-variable": "",
      "parameter": "",
      "function": ""
    }
  },
  "properties": {
    "fontSize": 0
  }
}

[pioupia]

Maybe implement a class ThemeBuilder or something like that.
This class will take either the above JSON object, or nothing. (Too complex sentence just for say: "The class will only take the above JSON object as an option.").

Then, we've methods like setColor(color_name, color_value), setFontSize(size) or setFontFamily(...) to load a font family for example.
I don't think we can add this functionality of loading a fontFamily in the JSON file.