GSIMap and poor NSArchiver performance

[Pierre-Yves Rivaille]

Hi,

it seems like there is a performance problem, when using GSIMapEmptyMap 
within NSArchiver.

GSIMapEmptyMap calls GSIMapCleanMap. GSIMapCleanMap does a lot of operations 
on the map buckets to be able to send a release to every key and every value. 
But all those costly operations are useless within NSArchiver because 
GSI_MAP_RELEASE_KEY GSI_MAP_RELEASE_VAL are set to empty.

I encountered this problem with a CVS version of GNUMail : the NSArchiver 
was archiving a graph of around 17000 objects and GSIMapCleanMap was taking 
around 5sec to clean everything on a p850.

I managed to make a quick fix for this, but it's so ugly I won't submit it.

        Pierre-Yves