Added function to calculate priority of buildings
The selection of task now takes into account the priority of the
building
Random walking no longer let the agents enter buildings
Trying to prevent damage from pos-shocks , fires and damaged buildings
Added fieryness to the calculus of priority
Fixed GasStation bug
Not taking into account buildings that have dead people inside
Merge pull request #16 from alandbarroso/firebrigade_priorities

Firebrigade priorities
Ajustes finais e redefinicao do valor de uma tarefa