Factor code out of main.cc and main.i into a bunch of files

so things are organized in a more sensible manner.  Take apart
finalInit and expose the individual functions which are now
called from python.  Make checkpointing a bit easier to use.

--HG--
extra : convert_revision : f470ddabbb47103e7b4734ef753c40089f2dcd9d

src/python/m5/main.py

@@ -240,7 +240,7 @@ def main():
         print "M5 Simulator System"
         print brief_copyright
         print
-        print "M5 compiled %s" % internal.main.cvar.compileDate;
+        print "M5 compiled %s" % internal.core.cvar.compileDate;
         print "M5 started %s" % datetime.now().ctime()
         print "M5 executing on %s" % socket.gethostname()
         print "command line:",
@@ -256,7 +256,7 @@ def main():
         usage(2)
 
     # tell C++ about output directory
-    internal.main.setOutputDir(options.outdir)
+    internal.core.setOutputDir(options.outdir)
 
     # update the system path with elements from the -p option
     sys.path[0:0] = options.path