Update of confirmation of actions
    
    This patch is changing confirmation of actions according to ticket #3035, see the ticket description.
    
    It does following changes:
     * Confirmation of update action was removed.
     * Action lists resets to first action (which is usually a NOP: '-- select action --') on change of displayed entry.
     * New confirmation dialog was implemented. It is used for action confirmation. It is used in IPA.action to replace the call of window.confirm(message). The old call is a modal window which blocks all JS functionality and has different style than other dialogs in Web UI. The new one has same design and doesn't block background operations.
    
     https://fedorahosted.org/freeipa/ticket/3035