Mentat

In mentat-reporter, https://github.com/derpston/python-simpleflock is used. It's not imported as a module, the source code from the repository is copied to our source code. What I don't like about the code is that it throws an exception if the lock cannot by acquired, and the error is emailed to system administrators. Is it necessary to send the emails?

Also, there are two approaches:
1. the script should detect if another instance of itself is running
2. file lock - can be implemented in the python script, like simpleflock, or maybe we can use flock from the system, so it would be something like */5 * * * * /usr/bin/flock /tmp/my.lock /usr/local/bin/myjob.

I like the second approach with flock, as it's the easiest and fastest to implement

The thing is, this will only affect executing jobs from crontab. It would still be possible to have multiple instances running at the same time if the script was executed manually. But I think it's OK. The scripts are not meant to be executed manually.

In e3ccafa4 I added flock to the scripts running multiple times a day. The ones running just once a day remained unchanged.