Implementation of the 3 classes of alarms in the fsm

[Nicogene]

Task Description

The three classes of alarms are the following(see #51):

• definitive: block the system and allow for atmospheric flow in fully passive mode, requires intervention from the user to solve problem and reset alarms.
• transitory: the ventilator can resume normal operation if the measured quantity falls back in the operating range, user must be aware of the alarm triggering which is used to identify possible problems
• derived: this is calculated from measured quantities, e.g. an alarm measuring the leakage from the mask as the difference from inspired and expired volumes.

These have to be translated in 3 states of the Alarms_handling sub-fsm.

Definition of Done

The states representing the 3 type of alarms have been added in the fsm

[pattacini]

The FSM has been refactored in view of the handling of the alarms.

No strings are handled, rather the FSM provides alarms id's as it turned out that strings are quite unwieldy to manipulate when it comes down to generate code.

[pattacini]

Closing as the skeleton is available by now.