Add users-settings collection and handle dynamic configuration

...l5/imports/api/meetings/server/modifiers/removeMeeting.js

bigbluebutton-html5/imports/api/users-settings/index.js

...uebutton-html5/imports/api/users-settings/server/index.js

...button-html5/imports/api/users-settings/server/methods.js

...orts/api/users-settings/server/methods/addUserSettings.js

...rts/api/users-settings/server/modifiers/addUserSetting.js

...api/users-settings/server/modifiers/clearUsersSettings.js

...ton-html5/imports/api/users-settings/server/publishers.js

bigbluebutton-html5/imports/startup/client/auth.js

bigbluebutton-html5/imports/startup/client/base.jsx

...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

...ml5/imports/ui/components/audio/audio-modal/container.jsx

...luebutton-html5/imports/ui/components/audio/container.jsx

...5/imports/ui/components/logout-confirmation/container.jsx

...luebutton-html5/imports/ui/components/media/container.jsx

bigbluebutton-html5/imports/ui/components/media/service.js

...n-html5/imports/ui/components/meeting-ended/component.jsx

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