Notifications of new models or updates from followed creators on API

[CesarCruzUtec]

There are some extensions for A1111 that uses the civitai API, one of the features some people request is the ability to download or update models of followed creators. The current method is to look it up manually at the civitai page and then search for it by name or by author in the extension. By adding this feature to the API it would be easier for us to get the new models.