+ pplWithPath:create:readOnly:
+ pplWithPath:fromPPLData:readOnly:
+ propertyListWithPPLData:

- contentsAsData
- detachFromFile
- flush
- initWithPath:create:readOnly:
- initWithPath:fromPPLData:readOnly:
- pushChangesToDisk
- rootDictionary
- save
- setCacheHalfLife: