HttpURLConnection already supports the ability to follow redirects
automatically or not, but a finer degree of control is required
among other reasons, for maintaining compatibility with teh MS JVM
plugin needs to mirror the MS behavior where (depending on configuration)
a redirect may cause a user dialog to popup to confirm the action.
This must be supported for legacy applets and the new redirection API
will be called by plugin. It will also be useful for other applications.