Using the Register class, one can register callbacks to manipulate options or check options afterwards.
These callbacks are stored in the Callbacks class (being a singleton) and should be called by the Settings class when appropriate.
The Settings class does not call them yet.
Changed a lot in the class structure of Settings:
* Settings is now a Singleton. Obtain a new instance by Settings::instance().
* options_description objects are now static, thus a help message can be printed even if the constructor of Settings failes
* As Settings has static members, a .cpp file became necessary, hence cmake should probably be run...
* Help messages can be printed with new help and helpConfigfile routines
adding new exception that is thrown whenever loading the settings fails.
this exception is caught in mrmc-cpp.cpp. If this happens, the program is terminated.
gereon
dehnert