since memoryMode was put into the System (from SimObject), things got broken - this...

since memoryMode was put into the System (from SimObject), things got broken - this fixes it so that changeToTiming/changeToAtomic works.

src/python/m5/SimObject.py:
    now that setMemoryMode is a method in System, need to convert the SimObject * _ccObject into a system ptr to call setMemoryMode.
src/sim/main.cc:
    need this conversion now.
src/sim/sim_object.hh:
    put the enum back into SimObject.
src/sim/system.hh:
    memoryMode is now a part of SimObject, need the ::'s

--HG--
extra : convert_revision : 0ade06957fa57b497798e1f50c237ca1badc821d