Make sure getModifiedItemAttr always returns an int, unless otherwise wanting None

In py2, you could compare None to an int and it would always be less than. Unfortunately in py3, this is no longer the case. Returning getModifiedItemAttr as 0 allows us to not do a huge refactor.

eos/modifiedAttributeDict.py

@@ -28,23 +28,23 @@ cappingAttrKeyCache = {}
 
 
 class ItemAttrShortcut(object):
-    def getModifiedItemAttr(self, key, default=None):
+    def getModifiedItemAttr(self, key, default=0):
         return_value = self.itemModifiedAttributes.get(key)
 
         if return_value is None and default is not None:
             return_value = default
 
-        return return_value
+        return return_value if default is not None else None
 
 
 class ChargeAttrShortcut(object):
-    def getModifiedChargeAttr(self, key, default=None):
+    def getModifiedChargeAttr(self, key, default=0):
         return_value = self.chargeModifiedAttributes.get(key)
 
         if return_value is None and default is not None:
             return_value = default
 
-        return return_value
+        return return_value if default is not None else None
 
 
 class ModifiedAttributeDict(collections.MutableMapping):