= ShardedMutex, aka 'not so bad global lock'

This library provides global locks for (pseudo-) atomic access to data without memory overhead per object. Concurrency is improved by selecting a Mutex from a pool based on the Address of the object to be locked.

Even being sharded, these Mutexes act still as global and non-recursive locks. One must not try to lock another object while a lock is already hold, otherwise deadlocks are around the corner.

There is one pool of mutexes per guarded type, thus it is possible to lock values of different types at the same time.