crawl_duration is a host specific property
crawl_duration is a host specific property

Only update crawl_duration at the end of crawl of a host
and not after each category. As it is a host specific property
it only makes sense to update it once.

pombredanne/mirrormanager2,pombredanne/mirrormanager2,pombredanne/mirrormanager2,pombredanne/mirrormanager2