Set newurl on admin actions to stay on the page
    
    By setting newurl, the browser state is replaced with the base configuration
    URL, so that user actions like hitting reload do not end up trying to
    trigger another change or an enablement/disablement of a plugin.
    It also insures actions are not accidentally triggered when hitting the back
    button.
    
    Signed-off-by: Simo Sorce <simo@redhat.com>
    Reviewed-by: Patrick Uiterwijk <puiterwijk@redhat.com>