LocationConverter constructor Null safety

1. irte_engine
2. location_json
3. LocationConverter
4. LocationConverter constructor

LocationConverter class

1. Constructors
2. LocationConverter
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. fromJson
13. fromJsonList
14. fromJsonListString
15. fromJsonString
16. toJson
17. toJsonList
18. toJsonListString
19. toJsonString