Mutex
=====

This example models mutual exclusion using mutex. 
Each "process" can be in either one of the following states:

n - general state
t - waiting for its turn to enter its critical section.
c - inside its critical section

When both processes are in state t , i.e. competing for hold of the mutex 
they are given control in turns i.e the mutex uses a queue to ensure 
mutual exclusion.