Switch from optparser to argparser for parsing command line arguments #6865
As stated in the optparser documentation, this module is deprecated in favour of argparser. It was an easy switch, as argparser is mostly backwards compatible except for some method name changes. Also, it is now possible to implement mutual exclusivity for some args, so it is not longer possible to combine -r and -q or --install and --install-silent options.
… as well as added choices for log level
…sed by add-ons or plugins.