Verbose output when multiple workers try running the same task(s)

Not fully backwards compatible: if you update the scheduler before the worker, you will have problems
The other way is fine though (updating the worker before the scheduler)

Also removed support for fallback to an older way of calling the scheduler - this was fixed in the scheduler in July 2013 so it should not be a problem.
Merge pull request #174 from erikbern/running-tasks-info

When you want to run tasks but they are currently run by other workers, ...