- saving json to string uses FFirstKeyId and FNextKeyId. fixed a bug that occurs if deleting keys from hashtable
- added defrag after key delete from an object
- added missing function Fill
- fixed division by zero in Roc computation
- changed IAssert to EAssert. IASserts cause app exit so they cannot be caught
- disabled snap importing (due to SWIG problems)
- removed registration of TTwitterGraph aggregator (due to SWIG problems)