meta: define Plugin Runtime

[yorkie]

The ML low-level API is the basic layer that provides the basic ML power for plugin developers.

• [x] datasets
  • [ ] split
  • [x] shuffle
  • [x] sample
• [ ] model
  • [ ] cv
  • [x] gray
  • [ ] random
  • [x] resize
  • [ ] nlp
  • [x] tokenize
  • [ ] tf/idf
• [ ] validation
  • [x] ar/ap
  • [ ] confusion matrix
  • [x] mAP
  • [ ] roc/auc
• [ ] utils
  • [ ] download
  • [ ] zip/unzip

[Txiaozhe]

Good idea