from_restore for NM models on HF plus popular properties
# What does this PR do ?

Add two popular read-only properties for tensor and pipeline parallelism values.
Change some of the self._cfg to self.cfg and cfg to self.cfg

Adds from_pretrained for NM Models on HF Hub

**Collection**: [Note which collection this PR will affect]
NLP

# Changelog 
- Add specific line by line info of high level changes in this PR.

# Usage

```python
# Add a code snippet demonstrating how to use this 
print(model.tensor_model_parallel_size)
rint(model.pipeline_model_parallel_size)
```

# Before your PR is "Ready for review"
**Pre checks**:
- [x] Make sure you read and followed [Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md)
