add script to train with ft (pytorch#1812)

Summary:
the script adds configuration options to run training locally with ft
enabled

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* pytorch#1840
* pytorch#1811
* pytorch#1810
* __->__ pytorch#1812
* pytorch#1809

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Co-authored-by: Tushar Jain <[email protected]>

Author: tushar00jain

torchtitan/models/llama3_ft/train_configs/debug_model.toml

@@ -91,3 +91,9 @@ num_fragments = 2
 semi_sync_method = "diloco"
 process_group = "nccl"
 process_group_timeout_ms = 10000
+<<<<<<< HEAD
+=======
+
+[experimental]
+custom_args_module = "torchtitan.components.ft.config"
+>>>>>>> f63037ff (add script to train with ft (#1812))