Create the slice experiments in a subgroup of GeniSlices, named by the
SA of the caller. This means we call out to the Emulab newgroup script to create a group if it does not exist. We also have to reset the groups of the GeniUser once we know the SA. Other small changes: * Minor module shuffling. * Use GetSiteVar() from emutil instead of libdb * Get rid of obsolete code referring to the old reservation holding experiment. * Cleanup logfiles in the workdir. * Capture output from the mapper and reformat error logging to make it more apparent to the caller what went wrong. * Change call to GeniSliver::Node->Create(); pass in the node object.