ColorUtils constructor Null safety

1. baguette
2. ColorUtils
3. ColorUtils
4. ColorUtils constructor

ColorUtils class

1. Constructors
2. ColorUtils
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. nextColor
13. withLightness