Stats & serialization tweaks & cleanup. Unserializing from

Stats & serialization tweaks & cleanup.  Unserializing from
a checkpoint now gives identical results to running from scratch
and doing at switchover at the same cycle!
- CPUs start at cycle 0 again, not cycle 1.
- curTick is now serialized & unserialized.
- Stats get reset in main (before event loop).  Since this is done
after curTick is unserialized, simTicks gets set correctly for
running from a checkpoint.
- Simplify serialization to happen in a single pass.
- s/Serializeable/Serializable/

arch/alpha/isa_traits.hh:
dev/etherlink.hh:
sim/eventq.cc:
sim/eventq.hh:
    s/Serializeable/Serializable/
kern/tru64/tru64_system.cc:
sim/process.cc:
    Make initial CPU activation on cycle 0 again (not 1).
sim/main.cc:
    Reset stats before getting started.
    Make error message on falling out of event loop
    more meaningful.
sim/serialize.cc:
sim/serialize.hh:
    Get rid of now-useless initial pass; serialization is
    done in a single pass now.
    Serialize & unserialize curTick.
    Wrap curTick and mainEventQueue in a "globals" Serializable object.
    s/Serializeable/Serializable/
sim/sim_object.cc:
    Add static function to serialize all SimObjects.
sim/sim_object.hh:
    Add static function to serialize all SimObjects.
    s/Serializeable/Serializable/

--HG--
extra : convert_revision : 9dcc411d0009b54b8eb61c3a509680b81b9f6f68