Cronjob breaks database if you aren't fully up to date first

[lukepighetti]

I haven't tested this extensively but it seems that if your 1 minute update chronjob triggers while the previous one is still running it wreaks havoc on the database forcing you to use the patch in #118

That is to say that you should do a full update before setting up your chronjob otherwise you'll spend a lot of time deleting tmp/index.pid

Again, this is a poorly formed issue submission but that's what I've got for now.

Thanks