Use KNI with external data and dictionary on the cloud

[bruno-at-orange]

Summary

• Use PLRemoteFileService to access dictionaries on cloud storage through FileSize and FileExists.
• Reading the dictionary from cloud storage already works.
• Reading the external table from cloud storage already works.
• Tested with KNIRecodeMTFiles with command:

KNIRecodeMTFiles \
  -d gs://AIDS/AIDSMolecule.kdic Molecule \
  -i /Users/bob/LearningTest/MTdatasets/AIDS/AIDSMolecules.txt 1 \
  -s Atoms /Users/bob/LearningTest/MTdatasets/AIDS/AIDSAtoms.txt 1 2 \
  -s Bonds /Users/bob/LearningTest/MTdatasets/AIDS/AIDSBonds.txt 1 2 3 \
  -x MoleculeLabel "" gs://AIDS/AIDSLabels.txt

Note

• I recommend releasing this feature after Allow the temporary directory to be located on the cloud #975. In the current state, dictionaries on cloud storage are first copied to a local temporary directory (not explicitly configured in KNI) and then read. With Allow the temporary directory to be located on the cloud #975, dictionaries will be read directly on cloud storage.
• KNITransfer is not cloud ready. It will be easy to to it after Allow the temporary directory to be located on the cloud #975 (need PLRemoteFileservice::OpenInputBinaryFile)