Get Port stuff working with full-system scripts.

Key was adding support for cloning port references (trickier than it sounds).
Got rid of class/instance thing and go back to instance cloning...
still don't allow changing SimObject parameters/children after a
class (instance) has been subclassed or instantiated (or cloned), which
should avoid bizarre unintended behavior.

configs/test/fs.py:
    Add ".port" to busses to get a port reference.
    Get rid of commented-out code.
src/python/m5/__init__.py:
    resolveSimObject should call getCCObject() instead of createCCObject()
    to avoid cycles in recursively creating objects.
src/python/m5/config.py:
    Get rid of class/instance thing and go back to instance cloning.
    Deep copy has to happen only on instance cloning then (and not on subclassing).
    Add getCCObject() method to force creation of C++ SimObject without
    recursively creating its children.
    Add support for cloning port references (trickier than it sounds).
    Also clean up some very obsolete comments.
src/python/m5/objects/Bridge.py:
src/python/m5/objects/Device.py:
    Add ports.

--HG--
extra : convert_revision : 4816d05ead0de520748aace06dbd1911a33f0af8

src/python/m5/__init__.py

@@ -107,11 +107,7 @@ env.update(os.environ)
 # Function to provide to C++ so it can look up instances based on paths
 def resolveSimObject(name):
     obj = config.instanceDict[name]
-    if not obj._ccObject:
-        obj.createCCObject()
-    if obj._ccObject == -1:
-        panic("resolveSimObject: recursive lookup error on %s" % name)
-    return obj._ccObject
+    return obj.getCCObject()
 
 # The final hook to generate .ini files.  Called from the user script
 # once the config is built.