added ability to enable forceReload.

[Diaglyonok]

forceReload can allow you to have always actual data. Without this fix I can not get new info after setState();

Example: I get initial state of some async task. Then i change some data and my async task will returns another value. But to have actual data i need to call reloadState(); manually. I thing it is uncomfortable. Now if you set reloadState = true It will call async task every build.

I found it useful for loading pictures from file storage. If you want, you can merge it, maybe someone will need this opportunity too)