Added PSO example
Corrected PSO example

There are now no hb cycles with one thread doing reorderings.
Removed unused header
Bugfix in Peterson example
Fixed a typo in NBW example
Fixed typos in the Cilk example
Added one more Cilk example
Fixed Lamport's example: process ids must be positive
Fixed inconsistency about required Boost version
Fixed CLH lock
Fixed MCS lock
Code cleanup
More refactoring
NotBlocked -> CanAccessMemory
Make assertions unconditionally enabled
Got rid of foreach
Got rid of unused NaivePrinter
First attempt to implement trench::SCSemantics
Faster SC reachability
Favourite thread heuristic