Add tile log analysis

This adds a process which runs a cron job processing the tile logs into summaries of "z/x/y count" daily.
(a) Yes, I put it in because I kept getting annoyed by the temporaries showing up as untracked.
(b) I'm not sure I understand - why would you want these to show up as untracked when it's not like anyone should commit them? Indeed, if they are not ignored then often people commit them by mistake when doing a `git add -A` (which is something that IMHO shouldn't be done, but people will do it anyway).