| Add(UserUnitInfo) | Add user unit to unit provider |
| Add(eumItem, eumUnit) | Add user unit to unit provider, based on eumItem type |
| Add(UserUnitProviderUnitSearchType, UserUnitInfo) | Add user unit to unit provider, with the given search type |
| Add(String, eumItem, eumUnit) | Add user unit to unit provider, based on Id of quantity |