fixed Bug 1014568 - added BotoS3 cache of connection & bucket - single bucket days

On looking at the benchmarking of the individual calls to the BotoS3 API, and knowing that it is really a RESTful interface, I surmised that the connection and bucket object actually carry no state.  That  means they can be cached and reused.  I added caching of the connection and bucket objects and this appears to have sped things up by more than an order of magnitude.