Revert "llama_cpp server: prompt is a string". Closes #187

This reverts commit b9098b0.

Author: abetlen

llama_cpp/server/app.py

@@ -167,8 +167,9 @@ def get_llama():
 )
 
 class CreateCompletionRequest(BaseModel):
-    prompt: Optional[str] = Field(
-        default="", description="The prompt to generate completions for."
+    prompt: Union[str, List[str]] = Field(
+        default="",
+        description="The prompt to generate completions for."
     )
     suffix: Optional[str] = Field(
         default=None,
@@ -222,6 +223,9 @@ class Config:
 def create_completion(
     request: CreateCompletionRequest, llama: llama_cpp.Llama = Depends(get_llama)
 ):
+    if isinstance(request.prompt, list):
+        request.prompt = "".join(request.prompt)
+
     completion_or_chunks = llama(
         **request.dict(
             exclude={