Add maisi controlnet training

[guopengf]

Fixes # .

Description

Add training script for MAISI ControlNet.

Checks

• [ ] Avoid including large-size files in the PR.
• [ ] Clean up long text outputs from code cells in the notebook.
• [ ] For security purposes, please check the contents and remove any sensitive info such as user names and private key.
• [ ] Ensure (1) hyperlinks and markdown anchors are working (2) use relative paths for tutorial repo files (3) put figure and graphs in the ./figure folder
• [ ] Notebook runs automatically ./runner.sh -t <path to .ipynb file>

[mingxin-zheng]

Hi @guopengf , can we have some doc-string added in the functions? Thanks!

[guopengf]

Hi @guopengf , can we have some doc-string added in the functions? Thanks!

Hi @mingxin-zheng, thanks for the comments. I added docstring for util functions.

[mingxin-zheng]

@KumoLiu I don't have any further comments except the ones above.

[guopengf]

Hi @KumoLiu and @mingxin-zheng, thanks for the valuable comments! I addressed them in the latest commit. In addition, I moved utility functions used in the controlnet training script to scripts/utils.py since I found Can's PR has been merged.