[PCB] Make it a PreCompiled module

The ProgramControlBlock is now a pre-compiled class, which allows to speed-up
programs compilation time.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>
[Headers] Clean-up pre-compiled headers

The headers to be pre-compiled are not just these regarding product
generated entitied: i.e. Steps, SyncBarriers and PCBs.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>