Merge pull request #3939 from KDSBrowne/userlist-accessibility

...mports/ui/components/actions-bar/emoji-menu/component.jsx

...button-html5/imports/ui/components/dropdown/component.jsx

...n-html5/imports/ui/components/dropdown/list/component.jsx

...l5/imports/ui/components/dropdown/list/item/component.jsx

...5/imports/ui/components/dropdown/list/title/component.jsx

...tml5/imports/ui/components/dropdown/trigger/component.jsx

...rts/ui/components/nav-bar/settings-dropdown/component.jsx

...ton-html5/imports/ui/components/user-avatar/component.jsx

...orts/ui/components/user-list/chat-list-item/component.jsx

...mports/ui/components/user-list/chat-list-item/styles.scss

...utton-html5/imports/ui/components/user-list/component.jsx

...orts/ui/components/user-list/user-list-item/component.jsx

bigbluebutton-html5/imports/utils/keyCodes.js

bigbluebutton-html5/private/locales/en.json