Consider moving config from /etc/default to /etc/config for inclusion in OpenWRT backup archive

[dgroenen]

Thanks for this great piece of software!

Currently, snapclient on openwrt installs a config file in /etc/default/snapclient. This file is lost on OpenWRT upgrade (sysupgrade). By moving the config file to /etc/config, it gets included and restored through the OpenWRT config backup mechanism.
Alternatively, a symlink from /etc/default/snapclient could be made to /etc/config/snapclient.