Change Details

* [ ] Remove boilerplate code from PPTP server implementation * [ ] Remove IPv4/IPv6 name-server nodes from CLI and migrate to common `name-server` node * [ ] Migrate RADIUS config to common include

* [x] Remove boilerplate code from PPTP server implementation * [x] Remove IPv4/IPv6 name-server nodes from CLI and migrate to common `name-server` node * [x] Migrate RADIUS config to common include

* [ * [x] Remove boilerplate code from PPTP server implementation * [ * [x] Remove IPv4/IPv6 name-server nodes from CLI and migrate to common `name-server` node * [ * [x] Migrate RADIUS config to common include