Draft: Open source export module
Closing this since opened a new one
# What does this PR do ?

Open sourcing the export and deploy module that exports a nemo checkpoint to TensorRT-LLM and serves it using PyTriton.

**Collection**: [None]

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

# Usage
* You can potentially add a usage example below

```python

# A simple example is as follows. 

# Run the following on the server side

from nemo.export import TensorRTLLM
from nemo.deploy import DeployPyTriton

# To export to TRT-LLM

trt_llm_exporter = TensorRTLLM(model_dir="/path/to/trt_llm_engine_folder")
trt_llm_exporter.export(
    nemo_checkpoint_path="/path/to/nemo/ckpt.nemo",
    model_type="model_type",
    n_gpus=1,
)

# To start serving on Triton server

nm = DeployPyTriton(model=trt_llm_exporter, triton_model_name="LLM")
nm.deploy()
nm.run()

# To query the model, please run the following on a the client side

from nemo.deploy import NemoQuery

nq = NemoQuery(url="localhost:8000", model_name="LLM")
output = nq.query_llm(
    prompts=["what is the color of a banana?"], , top_k=1, top_p=0.0, temperature=1.0,
)

```

# Jenkins CI
To run Jenkins, a NeMo User with write access must comment `jenkins` on the PR.

# 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)
- [x] Did you write any new necessary tests? (Test location: https://github.com/oyilmaz-nvidia/NeMo/blob/oss-export/tests/export/test_nemo_export.py) 
- [x] Did you add or update any necessary documentation? (Added documentation on the gitlab repo for the docs. Will need to make some updates though)
- [ ] Does the PR affect components that are optional to install? (Ex: Numba, Pynini, Apex etc)
  - [ ] Reviewer: Does the PR have correct import guards for all optional libraries?
  
**PR Type**:
- [x] New Feature
- [ ] Bugfix
- [x] Documentation

If you haven't finished some of the above items you can still open "Draft" PR.


## Who can review?

Anyone in the community is free to review the PR once the checks have passed. 
[Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md) contains specific people who can review PRs to various areas.
