scripts / DynDNS

(closes #7)

Addressed error message: Experimental splice on scalar is now forbidden

- fixed handling of expiry
- fixed calculation of expiry period
- reduced CNAME checks / lookups to when really needed

Implemented consistent output (normally provide an HTTP response when 
usual things go wrong)
Hid detailed error information in debug info so that end users cannot 
see this

new functionality:
  - ability to load a config file (no more hard-coding settings) that 
can be optional, required or ignored
  - added RecordTTL setting (used to be hard-coded to 1h)

Fixes:
  - ExpireAfter now also accepts just a number of seconds (without unit 
s)

Other changes:
  - AllowDebugKey now defaults to 'off'
  - UpdateTXT and DeleteTXT no longer need a trailing whitespace
  - sanitized perodSeconds so that it only does a single multiplication

Changed the behaviour of the update command so that it would not just 
pick the remote address if no ip parameter was provided.

To autodetect the IP address it is now mandatory to pass value auto (so 
ip=auto) for the ipv4addr or ipv6addr. This also allows to specify which 
address should be autodetected and have a static address passed for ipv4 
and have the ipv6 address autodetected for multi-network systems (also 
closes #6)

(closes #2)

list - show contents of a domain (was view)
  view - show a single entry (was status)

…th have a value (if not, abort with an HTTP 400 errro)

renamed LICENSE file for clarity