Add TimesURL

[WenjieDu]

1. Model description

TimesURL should be included in PyPOTS, and could start from the imputation task.

@article{liu2024timesurl,
title={{TimesURL}: Self-Supervised Contrastive Learning for Universal Time Series Representation Learning},
author={Liu, Jiexi and Chen, Songcan},
volume={38},
url={https://ojs.aaai.org/index.php/AAAI/article/view/29299},
DOI={10.1609/aaai.v38i12.29299},
number={12},
journal={Proceedings of the AAAI Conference on Artificial Intelligence},
year={2024},
month={Mar.},
pages={13918-13926}
}

2. Check open-source status

• The model implementation is publicly available

3. Provide useful information for the implementation

https://github.com/Alrash/TimesURL