[dev] trivial patch for nag summary date format

[Chuck Hagenbuch]

Quoting Mathieu CLABAUT <mathieu.clabaut at free.fr>:

>   here is a trivial patch to add suport for date format preferences in
>   task summary (the default was way too long)...
> 
>   Say if I must post it to nag dev list (I did not subscribe to it..)

Committed, thanks.

-chuck

--
Charles Hagenbuch, <chuck at horde.org>
must ... find ... acorns ... *thud*