Suport fire in Lab Recruits random EFSM generator

[deid00]

The EFSM model implemented in MBT supports the definition of fire and death for a Lab Recruit model. An example is given in class ButtonDoors1FireWithDeath. We would like to add the possibility to the user to add a random number of fire objects in the Lab Recruits random EFSM generator.
The fire should be placed in a corridor before a door, to force the agent to pass through it before going to the door.