Multiple configfile-related changes - Print current configfile in the output of 'env' (this also makes configfile changeable in runtime via 'setenv') - In 'configfile' commands, print which config file is being used - Fix behavior of existing 'more_conf' - Make load_config() return filename and hash, rather than unconditionally overwrite $conf - Bring back %conf2 into implementation of save_config; it is necessary to be there or 'configfile' is getting lost/deleted in the runtime config Other changes - Add 'set' as alias for 'setenv' - Add unsetenv/unset (opposite of setenv/set) - Do not print unset/undefined values in 'env'