move screenshare alert to service / fit audio alert on meeting end

...ton-html5/imports/ui/components/actions-bar/component.jsx

...ton-html5/imports/ui/components/actions-bar/container.jsx

...rts/ui/components/actions-bar/desktop-share/component.jsx

...ton-html5/imports/ui/components/screenshare/component.jsx

...ton-html5/imports/ui/components/screenshare/container.jsx

...button-html5/imports/ui/components/screenshare/service.js