Image2vector

- The convert mode can be customized
- Support custom preprocess func function for image preprocessing

- The batch_size and num_workers parameters can be customized

- support many backends, default cpu

- add numpy dep in setup.py
- gen_vector support args type: bytes

- fixbug: `ANTIALIAS is deprecated and will be removed in Pillow 10 (2023-07-01). Use Resampling.LANCZOS instead.`, look at https://www.reddit.com/r/learnpython/comments/uxb8b4/help_pillow_deprecation_warning/
- fixbuf: `The parameter 'pretrained' is deprecated since 0.13 and may be removed in the future, please use 'weights' instead.`, look at https://github.com/JaidedAI/EasyOCR/issues/766

- fixbug: `output with shape [1, 426, 512] doesn't match the broadcast shape [3, 426, 512]`