Ideas

• Allow one-time task parameters that are deleted after execution.
• Implement task condition: run if prev is OK, run if prev FAILED
• Implement runtime input parameters, e.g. results of a function or an arbitrary query.
• Add pipeline machinery, e.g. output of the previous task is the input for the next one.
• Add concept of tasks secrets to store passwords, connection credentials, etc.
• Add tasks_tidy function to clear unused tasks.
• Implement multi-node functionality #179