Added: Browser, setRequestIntervalLimitGlobal(host, i, x, y) allows for a window of requests without waiting until threshold has been reached. Then on after it respects wait int.
Added: K2SApi, 
- setRequestIntervalLimitGlobal support
- Thread.sleep && re-request on 429 header.

git-svn-id: svn://svn.jdownloader.org/jdownloader/browser@26822 ebf7c1c2-ba36-0410-9fe8-c592906822b4