Scheduler

For the first step in building precompute functionality into Jia, this pull request introduces a general purpose task scheduler. See [jia/scheduler/README](https://github.com/Locu/kronos/blob/scheduler/jia/scheduler/README.md) for a sample.
It is an if/else because this way if there are 18 tasks scheduled to launch, it will launch them all at the same time rather than 1 second apart.