[Ddclient-support] Patch: Treat --daemon values as intervals

[<ja...@hu...>]

Attached is a patch to r27 of ddclient.  The patch changes --daemon values to
be intervals all of the time, instead of intervals some of the time and
number of seconds the rest of the time.

This fixes a fairly nasty bug, where values such as '5h' were treated as
zero by the 'sleep' function.

- James