v5.0.0

• Added:
  • Add the method UnregisterOpts for OptGroup to unregister the registered options.
  • Add the method LoadDataSetCallback for Config to be used the watcher of the source.
• Changed:
  • Set, UpdateValue and UpdateOptValue return an error if failing to update the option.
  • LoadMap, LoadDataSet, , return an error if failing to load the configurations.
  • RegisterOpts panics instead of returning the bool if the option has been registered.
  • Snapshot no longer contains the default values of the options.
  • Move the type XXXOptField to the sub-package field.
  • Change the signature of the method Watch of Source from
    Watch(load func(DataSet, error), close <-chan struct{})
    to
    Watch(load func(DataSet, error) bool, close <-chan struct{})
• Removed:
  • Remove the field Callback from DataSet.
  • Remove the method RegisterOpt from OptGroup.
  • Remove the observer of the opt registering, that's ObserveRegister.
  • Remove the methods LoadSourceAndCallback and LoadSourceAndCallbackWithoutWatch from Config.