Optimize load time of update nodes recipe

Hi there,

this is one of the changes we did at T-Labs as mentioned in my [blog post](http://blog.hendrikvolkmer.de/2012/09/26/crowbar-at-scale/).

We could not find out why each node object was reloaded after the search. It worked for us if we just used the node object that was returned by the search. This way loading of the recipe is obviously way faster. If the re-loading of the node object is indeed needed, please disregard this pull-request and add a comment that explains the reload instead.

Cheers,
Hendrik