Merge pull request #7606 from Tainan404/issue-7556

.../meetings/server/methods/toggleWebcamsOnlyForModerator.js

...ton-html5/imports/api/users/server/handlers/userJoined.js

...utton-html5/imports/api/users/server/modifiers/addUser.js

...-html5/imports/api/video/server/modifiers/sharedWebcam.js

...tml5/imports/api/video/server/modifiers/unsharedWebcam.js

bigbluebutton-html5/imports/ui/components/app/component.jsx

...utton-html5/imports/ui/components/lock-viewers/service.js

...components/video-provider/many-users-notify/component.jsx

...components/video-provider/many-users-notify/container.jsx

...i/components/video-provider/many-users-notify/styles.scss

...orts/ui/components/video-provider/video-button/service.js

...luebutton-html5/imports/ui/services/notification/index.js

bigbluebutton-html5/imports/ui/services/user/mapUser.js

bigbluebutton-html5/private/config/settings.yml

bigbluebutton-html5/private/locales/en.json