ddns-scripts: new Version 2.1.0-2

- moved /usr/lib/ddns/dynamic_dns_lucihelper.sh from luci-app-ddns into this package
	(Github openwrt/luci issue 251)
	(OpenWrt Trac tickets 18326 18347)
- fix: dynamic_dns_update.sh did not loop
	(OpenWrt Trac ticket 18336)
- add provider cloudflare.com IPv4 and IPv6 (Thanks to Paul for support and testing)
	(OpenWrt Trac ticket 12500)
- modified detection, if dynamic_dns_fuctions are used by dynamic_dns_lucihelper.sh
- redirect stdout of wget,curl,host,nslookup,nc etc to /tmp/ddns_$$.dat and *.err instead of variables
- extended error detection in get_local_ip function
- modified verify of option ip_script to allow parameters, when calling
- add provider selfhost.de IPv4
- add provider no-ip.pl (nothing to do with no-ip.com)
	(Github openwrt/packages issue #542)
	IPv4 (tested) and also added for
	IPv6 (NOT tested) because client IP is autodetected be provider
- add getlocalip_sample.sh as sample script for usage of
	option ip_source 'script'  together with
	option ip_script '/usr/lib/ddns/getlocalip.sh -4'
- cleanup whitespaces at line ends

Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>