jeasonlzy/okhttp-OkGo ? reverse-engineered prompt

Build me an Android networking library and a simple demo app for it.

I want a clean, easy to use request framework built on top of OkHttp, with a REST style API that feels simpler than using raw networking code directly. It should support normal GET and POST requests, file upload and batch upload, plus batch download with pause and resume. Please include support for both RxJava and RxJava2, and let me plug in custom cache behavior too.

The demo app should show the common request flows in a way that is easy to test, with a few screens or examples for text requests, JSON responses, downloads, uploads, and cache handling. Keep it organized so the core library is separated from the optional Rx and server related parts.

If you need to check current docs or best practices for OkHttp and Android networking, look them up online before finishing.