Set heading to a static 180 for each agent for testing purposes.  Intigrated simulated annealing for selecting the number of weights to mutate, which is the same as the egreedy value.  Init weights on nn to be between -.2 and .2.  Changed the heading in rovers.py to use tan2 even though it is currently commented out.  .... I made the number of agents, pois, and episodes small for testing purposes.