GPT4All API Scaffolding. Matches OpenAI OpenAPI spec for chats and completions (#839)

* GPT4All API Scaffolding. Matches OpenAI OpenAI spec for engines, chats and completions

* Edits for docker building

* FastAPI app builds and pydantic models are accurate

* Added groovy download into dockerfile

* improved dockerfile

* Chat completions endpoint edits

* API uni test sketch

* Working example of groovy inference with open ai api

* Added lines to test

* Set default to mpt

gpt4all-api/gpt4all_api/app/api_v1/routes/health.py

@@ -0,0 +1,12 @@
+import logging
+from fastapi import APIRouter
+from fastapi.responses import JSONResponse
+log = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/health", tags=["Health"])
+
+
+@router.get('/', response_class=JSONResponse)
+async def health_check():
+    """Runs a health check on this instance of the API."""
+    return JSONResponse({'status': 'ok'}, headers={'Access-Control-Allow-Origin': '*'})