Clear cache on element update

[Zaborskih]

Hello,

It will be great to clear resource cache if elements are added/updated as it was in first version.
In development I refresh page after changes in elements and it's very annoying when everything is cached and you have to clear cache or mark resource as uncachable to see changes.

It can be done optional in settings if there are any concerns.

For now I've fixed my local version of plugin (by adding flag if something added or changed, and clearing cache in the end if flag is true).

Thanks!