The Resource.js xhr miss timeout option

1. A concise explanation of the problem you’re experiencing.

I hope Resource.js can provide a options to customize the xhr timeout.

2. A minimal code example. If you’ve found a bug, this helps us reproduce and repair it.

none.

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

Want to request to return as soon as possible, when the service is not available.

4. The Cesium version you’re using, your operating system and browser.

1.50

What sort of customization do you mean? It looks like you can currently set the retry attempts on a resource object:

https://cesiumjs.org/Cesium/Build/Documentation/Resource.html?classFilter=Resource

If you have a specific idea for how to improve this, we’d be happy to have a contribution! Check out the contributing guide: https://github.com/AnalyticalGraphicsInc/cesium/blob/master/CONTRIBUTING.md