Read config from an external source, and use that to modify the set of arguments.
Read config from an external source, and use that to modify the set of arguments. The "original" arguments are given as an argument to this function, so that this method can base its behavior on those arguments. (Eg., it can take a filename from those args.) It should return the complete set of args that should be used. It is free to choose to completely replace the original args, append to them, modify them, etc.
in general, implementations should be abstract override with a call to super, to allow multiple external configs via the Stackable Trait Pattern
save the config back to the external source.
save the config back to the external source. Any parameters for this method should have already been extracted from the call to readArgs
as with readArgs, this should in general be implemented as an abstract override with a call to super
Some external source of config information. It both allows config to be read from, and saved to, some external format.