pySim/ara_m: move code from do_aram_ to static methods
The method do_aram_store_ref_ar_do and do_aram_delete_all, which are part of the nested AddlShellCommands class, may be moved into the parent class as a static method, just like the already existing get_config method.
This makes the functionality re-usable to callers that do not use the CMD2 API.
