Implement hangup from Flash.
Implement hangup from WebRTC
Add isMuted function
Added isMuted function
Installed npm copy module with "npm install grunt-contrib-copy --save-dev" command
Added the following tasks :
- dev : to build a development version
- pushdev : to publish the development version and make it accessible
            through the HTTP server
- pushdist : to publish the main version and make it accessible
            through the HTTP server