fix the problem where the user shares two cameras, then unshare one of them, and a new user receives hasStream=false for that particular user

An array is used to store the stream names, instead of using a single string to
store them all.

All icons are now loaded from the CSS styles.

TODO: Fix problems with webcam icon

Conflicts:
	bigbluebutton-client/branding/default/style/css/BBBDefault.css
	bigbluebutton-client/src/BigBlueButton.mxml
	bigbluebutton-client/src/org/bigbluebutton/main/model/users/NetConnectionDelegate.as
	bigbluebutton-client/src/org/bigbluebutton/modules/users/views/MediaItemRenderer.mxml
	bigbluebutton-client/src/org/bigbluebutton/modules/videoconf/maps/VideoEventMapDelegate.as
	bigbluebutton-client/src/org/bigbluebutton/modules/videoconf/views/AvatarWindow.mxml
	bigbluebutton-client/src/org/bigbluebutton/modules/videoconf/views/ToolbarPopupButton.mxml

 - fix issue where a user is duplicated when calling in because the 3rd-party app passed an external userid

Renamed 'WebRTC' -> 'WebRTC Audio' so users have a better chance of knowing what this indicator means

minor client updates

Fix the 'timestretch' fixup so that seeking is done after stretching

The previous version may have the beginning of the audio off by a bit,
since it was seeking in the audio file to find the start before the
stretch was applied.