Cache profile info

For better performance when showing the user's own profile Overview / Match History / Replays etc pages, and similarly for when they look at a different user's. When they look at a profile again, it can show the cached info but say e.g. "Refreshing..." while it gets the latest info, then display the latest info and get rid of "Refreshing...". Maybe also have a way to forcefully clear the cached info in case of bugs or version compatibility problems etc, e.g. via Settings. It would be good if the cache could persist even if w3champions is restarted, so long as it doesn't later lead to cache data version compatibility problems if the format changes later.