Merge pull request #2748 from capilkey/add-checkbox-chat-sounds

...uebutton-client/branding/default/style/css/BBBDefault.css

bigbluebutton-client/locale/en_US/bbbResources.properties

...button-client/resources/prod/lib/bbb_webrtc_bridge_sip.js

...nt/src/org/bigbluebutton/main/views/FlashMicSettings.mxml

...rc/org/bigbluebutton/main/views/MainApplicationShell.mxml

...igbluebutton/modules/chat/events/ChatNoiseEnabledEvent.as

...c/org/bigbluebutton/modules/chat/views/AddChatTabBox.mxml

...nt/src/org/bigbluebutton/modules/chat/views/ChatView.mxml

...uebutton/modules/present/ui/views/PresentationWindow.mxml