Gruntfile.js: uglify once, copy twice
Gruntfile.js: uglify once, copy twice

This trims roughly 1 second from `grunt build`

joseph-onsip/SIP.js,josephfrazier/SIP.js,ronlobo/SIP.js,onsip/SIP.js,Escaux/SIP.js,onsip/SIP.js,markandrus/SIP.js