- implemented update request processing
- separated host and domain name in config (req. for DNS updates)
- enhanced NFT update validation
- cleaned up example user
- cleand up logging in update request
- moved appropriate config into user request struct
- Simplified UpdateRequest to the minimum required
- renamed test user to example
- removed user property from yml config, it is given by the file name.
- splitted server code analogous to command line code so that each handler has its own file.
- made viper confgi in userconfig internal
- added validation to userconfig
- added helper to combaine an IID with a v6net in userconfig
