push with code for relevance detector

[tanishq-ids]

Added Relevance Detector Code.

1. One Python script, make_training_data_from_curator.py, to generate data from the curator.
2. Another Python notebook, train_sentence_transformer.ipynb , trains a hugging face model with data generated from 1. and saves it locally.
3. Another script inference.py to have the inference of the model trained in 2.
4. Inference_demo.ipynb to get a working demo of 3.