Create cron run command

Support cron command like we had on version 1.0.

```bash
$ insulin help cron-run
Run system cron jobs.
Examples:
 insulin cron-run Runs all active jobs who are able to be executed according to their last 
run time.
 insulin cron-run --force Runs all jobs without checking last run time.
 insulin cron-run --jobs=1,2,3 Runs cron for job with Ids 1, 2 and 3.
Options:
 --jobs A comma delimited list of job ids.
 --force Force jobs to run without checking last run time.
```