Multiple prioritized concurrencty

[ssardina]

The current implementation assumes only one prioritized interrupt construct.

So one cannot start one prioritized and finish it, and then later start another one. The fluent interrupt_running will be false.

Also there will be problems if we have different prioritized interrupts running in different concurrent || branches. We need to have different interrupt_running(N) fluents to track each independently.

This is in page 123 in the CONGOLOG paper.