[Reviewe Andy] Fixes for broken sstable bulk provisioning

Andy

Can you review these fixes for me.  I've tested them by patching them on to an existing Homestead node then running through the bulk provisioning process.

Note that you now have the choice of specifying homer, homestead-local and homestead-hss when generating the sstables.  homestead-local generates both the cache and provisioning tables, homestead-hss only generates the cache tables.  I've verified that I can provision 1M subs with all three of homer, homestead-hss and homestead-local on an m1.medium instance.

I still want to make some ease of use improvements.  I'd like to make it a one stage process by collapsing the Python step into the Java tool (particularly since the Python step is slow compared to the Java bit), I'd like to have the Java tool pre-built in our images, and I think it would also be good to support number ranges in the csv file.

Mike