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.
What does HEAD actually equate to? Surely it only has meaning in the context of an existing checkout because it means the head of the current branch and the whole point here is that we are specifying what branch or tag to follow.

I you mean master, then please say "master" here, but maybe we should be following a tag instead so that changes don't autodeploy?