* Add new tables to store NS files (and any files they source) in the
DB alongside the resource records. Previously, we stored only the nsfiles for current experiments, and purged them when the experiment was terminated. The new approach saves them forever using the resource record ID. Note that we do not store copies of NS files, but reference them indirectly instead so that we can MD5 them and avoid the dups. I put a "compressed" bit into the table cause at some point we will start compressing the data before storing them into the DB. Or maybe we bag this and start using GFS! Also note that this addresses the problem of losing the NS file history when using swapmod, since the NS file is overwritten. * Add a pmapping table stores the nodes (and their types) used by an experiment. This data is also saved forever, alongside the resource records, so that we can more accurately replay an experiment. As Rob points out, the node names can also be used in conjunction with the ptop files that are saved, to get a 100% accurate remap of resources.