MFTCoder v0.3.0: Support more open source models, support Self-Paced Loss, support FSDP

Updates:

1. Mainly for MFTCoder-accelerate.
2. It now supports more open source models like Mistral, Mixtral(MoE), DeepSeek-coder, chatglm3.
3. It supports FSDP as an option.
4. It also supports Self-paced Loss as a solution for convergence balance in Multitask Fine-tuning.