Merge remote-tracking branch 'upstream/v2.0.x-release' into toast-notifications

...n-client/src/org/bigbluebutton/main/views/MainCanvas.mxml

...es/screenshare/view/components/ScreenshareViewWindow.mxml

...on-html5/imports/api/users/server/modifiers/clearUsers.js

...ebutton-html5/imports/ui/components/nav-bar/component.jsx

...ml5/imports/ui/components/notifications-bar/container.jsx

bigbluebutton-html5/imports/utils/humanizeSeconds.js