Updated tgi_model and added parameters for endpoint_model (#208)
* Added image url parameter
* Fixed up tgi model config
* Undid tgi available check
* Adjust tgi parameter names, and checked for attr existence
* Fixed task Id in argparse
* Removed obfuscation from private functions, to allow inheritance to override
* Updated tgi model to inherit from endpoint and just modify client calls
* Added option to specify model id in config for tgi model
* Added option to specify custom env vars
* Updated env vras
* Applied ruff format
* Added docs + readme
* Ruff format